An evolution of Solomon's K3 frame kit, this frame kit is designed for 3.5" quads that are not only robust but also very convenient for replacing broken arms.

• Wheelbase : 174.2mm 
• Total thickness of arms and bottom plates : 6mm (3mm each)
• Thickness of top and side plates : 2mm
• Motor mount : φ9-12mm, M2 (2pcs. each)
• FC mount : 25.5x25.5mm, 20x20mm, M2
• VTX mount :  25.5x25.5mm, 20x20mm, M2
• Stack height : 15mm
• Camera width :14mm
• Compatible with whoop style USB connector
• Built-in battery strap holder (can use up to 15mm width strap)
• Weight : Approx. 53g (Carbon only)
• Necessary Standoffs : 8 M2x15mm, 2 M2x14mm

If you need more stack height, use the optional side plates of 20mm height.

How to assemble :

The use of metal locknuts is strongly recommended. Each arm must be securely locked to prevent wobbling. In the picture below, the screw holes painted red need to be locked by metal locknuts, and the screw holes painted yellow are auxiliary ones to secure them if you are concerned about using heavy batteries. The screw holes painted blue are, of course, for the flight controller and the vtx.

Motor Mixer :

This frame has a wide-X shape, and the distance between the left and right motors is larger than the distance between the front and rear motors. As far as FPV flights are concerned, the flight characteristics of the wide-x frame can be quickly accustomed after a few flights and do not cause any inconvenience at all. However, in order to enjoy line-of-sight flights as well, I think it is necessary to set the motor mixer appropriately. The motor-to-motor distance of this frame is 130mm and 116mm; their ratio is 116/130 = 0.892.Therefore, the CLI command of Betaflight Configurator to properly set the motor mixer is as follows:

mixer custom
mmix reset
mmix 0 1 -1 0.892 -1
mmix 1 1 -1 -0.892 1
mmix 2 1 1 0.892 1
mmix 3 1 1 -0.892 -1 
save

Dimensions :

Lower Layer of Arms and Bottom Plates :

Upper Layer of Arms and Bottom Plates :

An evolution of Solomon's K3 frame kit, this frame kit is designed for 3.5" quads that are not only robust but also very convenient for replacing broken arms.

• Wheelbase : 174.2mm 
• Total thickness of arms and bottom plates : 6mm (3mm each)
• Thickness of top and side plates : 2mm
• Motor mount : φ9-12mm, M2 (2pcs. each)
• FC mount : 25.5x25.5mm, 20x20mm, M2
• VTX mount :  25.5x25.5mm, 20x20mm, M2
• Stack height : 15mm
• Camera width :20mm
• Compatible with whoop style USB connector
• Built-in battery strap holder (can use up to 15mm width strap)
• Weight : Approx. 53g (Carbon only)
• Necessary Standoffs : 8 M2x15mm, 2 M2x20mm

If you need more stack height, use the optional side plates of 20mm height and side plate spacers of 20mm height.

Although this kit is for DJI FPV 1G Camera, it is possible use a 19mm width camera by using two optional side plate spacers of 2mm thickness or DJI O3 camera by using those side plate spacers and two optional side plates designed to be used with iFlight's silicon damper for O3 camera.

How to assemble :

The use of metal locknuts is strongly recommended. Each arm must be securely locked to prevent wobbling. In the picture below, the screw holes painted red need to be locked by metal locknuts, and the screw holes painted yellow are auxiliary ones to secure them if you are concerned about using heavy batteries. The screw holes painted blue are, of course, for the flight controller and the vtx.

Motor Mixer :

This frame has a wide-X shape, and the distance between the left and right motors is larger than the distance between the front and rear motors. As far as FPV flights are concerned, the flight characteristics of the wide-x frame can be quickly accustomed after a few flights and do not cause any inconvenience at all. However, in order to enjoy line-of-sight flights as well, I think it is necessary to set the motor mixer appropriately. The motor-to-motor distance of this frame is 130mm and 116mm; their ratio is 116/130 = 0.892.Therefore, the CLI command of Betaflight Configurator to properly set the motor mixer is as follows:

mixer custom
mmix reset
mmix 0 1 -1 0.892 -1
mmix 1 1 -1 -0.892 1
mmix 2 1 1 0.892 1
mmix 3 1 1 -0.892 -1 
save

Dimensions :

Lower Layer of Arms and Bottom Plates :

Upper Layer of Arms and Bottom Plates :

An evolution of Solomon's K3 frame kit, this frame kit is designed for modular 3 to 3.5" heavier Toothpicks that are not only robust but also very convenient for replacing broken arms.

• Wheelbase : 148.6mm 
• Total thickness : 5mm (2.5mm each)
• Motor mount : φ9-12mm, M2 (2pcs. each)
• FC mount : 25.5x25.5mm, 20x20mm, M2
• Compatible with whoop style USB connector
• Built-in battery strap holder (can use up to 15mm width strap)
• Weight : Approx. 20g (Carbon only)

How to assemble :

The use of metal locknuts is strongly recommended. Each arm must be securely locked to prevent wobbling. In the picture below, the screw holes painted red need to be locked by metal locknuts, and the screw holes painted yellow are auxiliary ones to secure them if you are concerned about using heavy batteries. The screw holes painted blue are, of course, for the flight controller.

Motor Mixer :
This frame has a wide-X shape, and the distance between the left and right motors is larger than the distance between the front and rear motors. As far as FPV flights are concerned, the flight characteristics of the wide-x frame can be quickly accustomed after a few flights and do not cause any inconvenience at all. However, in order to enjoy line-of-sight flights as well, I think it is necessary to set the motor mixer appropriately. The motor-to-motor distance of this frame is 115.5mm and 93.5mm; their ratio is 93.5/115.5 = 0.810. Therefore, the CLI command of Betaflight Configurator to properly set the motor mixer is as follows:

mixer custom
mmix reset
mmix 0 1 -1 0.810 -1
mmix 1 1 -1 -0.810 1
mmix 2 1 1 0.810 1
mmix 3 1 1 -0.810 -1 
save

Dimensions :

Lower Layer :

Upper Layer :

An evolution of Solomon's K3 frame kit, this frame kit is designed for modular 3 to 3.5" heavier quads that are not only robust but also very convenient for replacing broken arms.

• Wheelbase : 148.6mm 
• Total thickness of arms and bottom plates : 5mm (2.5mm each)
• Thickness of top and side plates : 2mm
• Motor mount : φ9-12mm, M2 (2pcs. each)
• FC mount : 25.5x25.5mm, 20x20mm, M2
• VTX mount on Top Plate : 25.5x25.5mm, 20x20mm, M2
• Stack height : 15mm (enough to accept most AIO FC with a naked single PCB vtx)
• Camera width : 14mm
• Compatible with whoop style USB connector
• Built-in battery strap holder (can use up to 15mm width strap)
• Weight : Approx. 29g (Carbon only)
• Necessary Standoffs : 6 M2x15mm, 2 M2x14mm

How to assemble :
The use of metal locknuts is strongly recommended. Each arm must be securely locked to prevent wobbling. In the picture below, the screw holes painted red need to be locked by metal locknuts, and the screw holes painted yellow are auxiliary ones to secure them if you are concerned about using heavy batteries. The screw holes painted blue are, of course, for the flight controller.

Motor Mixer :
This frame has a wide-X shape, and the distance between the left and right motors is larger than the distance between the front and rear motors. As far as FPV flights are concerned, the flight characteristics of the wide-x frame can be quickly accustomed after a few flights and do not cause any inconvenience at all. However, in order to enjoy line-of-sight flights as well, I think it is necessary to set the motor mixer appropriately. The motor-to-motor distance of this frame is 115.5mm and 93.5mm; their ratio is 93.5/115.5 = 0.810. Therefore, the CLI command of Betaflight Configurator to properly set the motor mixer is as follows:

mixer custom
mmix reset
mmix 0 1 -1 0.810 -1
mmix 1 1 -1 -0.810 1
mmix 2 1 1 0.810 1
mmix 3 1 1 -0.810 -1 
save

Dimensions :

Lower Layer of Arms and Bottom Plates :

Upper Layer of Arms and Bottom Plates :

An evolution of Solomon's K3 frame kit, this frame kit is designed for modular 3 to 3.5" heavier quads that are not only robust but also very convenient for replacing broken arms.

• Wheelbase : 148.6mm 
• Total thickness of arms and bottom plates : 5mm (2.5mm each)
• Thickness of top and side plates : 2mm
• Motor mount : φ9-12mm, M2 (2pcs. each)
• FC mount : 25.5x25.5mm, 20x20mm, M2
• VTX mount on Top Plate : 25.5x25.5mm, 20x20mm, M2
• Stack height : 20mm (enough to accept most AIO FC with a naked digital vtx)
• Camera width : 14mm
• Compatible with whoop style USB connector
• Built-in battery strap holder (can use up to 15mm width strap)
• Weight : Approx. 29g (Carbon only)
• Necessary Standoffs : 6 M2x20mm, 2 M2x14mm

How to assemble :
The use of metal locknuts is strongly recommended. Each arm must be securely locked to prevent wobbling. In the picture below, the screw holes painted red need to be locked by metal locknuts, and the screw holes painted yellow are auxiliary ones to secure them if you are concerned about using heavy batteries. The screw holes painted blue are, of course, for the flight controller.

Motor Mixer :
This frame has a wide-X shape, and the distance between the left and right motors is larger than the distance between the front and rear motors. As far as FPV flights are concerned, the flight characteristics of the wide-x frame can be quickly accustomed after a few flights and do not cause any inconvenience at all. However, in order to enjoy line-of-sight flights as well, I think it is necessary to set the motor mixer appropriately. The motor-to-motor distance of this frame is 115.5mm and 93.5mm; their ratio is 93.5/115.5 = 0.810. Therefore, the CLI command of Betaflight Configurator to properly set the motor mixer is as follows:

mixer custom
mmix reset
mmix 0 1 -1 0.810 -1
mmix 1 1 -1 -0.810 1
mmix 2 1 1 0.810 1
mmix 3 1 1 -0.810 -1 
save

Dimensions :

Lower Layer of Arms and Bottom Plates :

Upper Layer of Arms and Bottom Plates :

An evolution of Solomon's K3 frame kit, this frame kit is designed for 3.5" quads that are not only robust but also very convenient for replacing broken arms.

• Wheelbase : 174.2mm 
• Total thickness of arms and bottom plates : 6mm (3mm each)
• Thickness of top and side plates : 2mm
• Motor mount : φ9-12mm, M2 (2pcs. each)
• FC mount : 25.5x25.5mm, 20x20mm, M2
• VTX mount on Top Plate :  25.5x25.5mm, 20x20mm, M2
• Stack height : 20mm (enough to accept most AIO FC with a naked digital vtx)
• Camera width : 14mm
• Compatible with whoop style USB connector
• Built-in battery strap holder (can use up to 15mm width strap)
• Weight : Approx. 45g (Carbon only)
• Necessary Standoffs : 6 M2x20mm, 2 M2x14mm

How to assemble :

The use of metal locknuts is strongly recommended. Each arm must be securely locked to prevent wobbling. In the picture below, the screw holes painted red need to be locked by metal locknuts, and the screw holes painted yellow are auxiliary ones to secure them if you are concerned about using heavy batteries. The screw holes painted blue are, of course, for the flight controller.

Motor Mixer :

This frame has a wide-X shape, and the distance between the left and right motors is larger than the distance between the front and rear motors. As far as FPV flights are concerned, the flight characteristics of the wide-x frame can be quickly accustomed after a few flights and do not cause any inconvenience at all. However, in order to enjoy line-of-sight flights as well, I think it is necessary to set the motor mixer appropriately. The motor-to-motor distance of this frame is 130mm and 116mm; their ratio is 116/130 = 0.892.Therefore, the CLI command of Betaflight Configurator to properly set the motor mixer is as follows:

mixer custom
mmix reset
mmix 0 1 -1 0.892 -1
mmix 1 1 -1 -0.892 1
mmix 2 1 1 0.892 1
mmix 3 1 1 -0.892 -1 
save

Dimensions :

Lower Layer of Arms and Bottom Plates :

Upper Layer of Arms and Bottom Plates :

An evolution of Solomon's K3 frame kit, this frame kit is designed for 3.5" quads that are not only robust but also very convenient for replacing broken arms.

• Wheelbase : 174.2mm 
• Total thickness of arms and bottom plates : 6mm (3mm each)
• Thickness of top and side plates : 2mm
• Motor mount : φ9-12mm, M2 (2pcs. each)
• FC mount : 25.5x25.5mm, 20x20mm, M2
• VTX mount :  25.5x25.5mm, 20x20mm, M2
• Stack height : 15mm
• Camera width : 19mm
• Compatible with whoop style USB connector
• Built-in battery strap holder (can use up to 15mm width strap)
• Weight : Approx. 53g (Carbon only)
• Necessary Standoffs : 8 M2x15mm, 2 M2x19mm

If you need more stack height, use the optional side plates of 20mm height and side plate spacers of 20mm height.

Although this kit is for 19mm width camera, it is possible to use 20mm width camera such as DJI FPV 1G camera by using two optional side plate spacers of 1.5mm thickness or DJI O3 camera by using two optional side plates designed to be used with iFlight's silicon damper for O3 camera.

How to assemble :

The use of metal locknuts is strongly recommended. Each arm must be securely locked to prevent wobbling. In the picture below, the screw holes painted red need to be locked by metal locknuts, and the screw holes painted yellow are auxiliary ones to secure them if you are concerned about using heavy batteries. The screw holes painted blue are, of course, for the flight controller and the vtx.

Motor Mixer :

This frame has a wide-X shape, and the distance between the left and right motors is larger than the distance between the front and rear motors. As far as FPV flights are concerned, the flight characteristics of the wide-x frame can be quickly accustomed after a few flights and do not cause any inconvenience at all. However, in order to enjoy line-of-sight flights as well, I think it is necessary to set the motor mixer appropriately. The motor-to-motor distance of this frame is 130mm and 116mm; their ratio is 116/130 = 0.892.Therefore, the CLI command of Betaflight Configurator to properly set the motor mixer is as follows:

mixer custom
mmix reset
mmix 0 1 -1 0.892 -1
mmix 1 1 -1 -0.892 1
mmix 2 1 1 0.892 1
mmix 3 1 1 -0.892 -1 
save

Dimensions :

Lower Layer of Arms and Bottom Plates :

Upper Layer of Arms and Bottom Plates :

This is a variation of "SOLOMONS K3B TYPE1 KIT".  The built-in hook for rubber band has been eliminated, and mounting holes (30.5x30.5mm, M2) have been added for convenient use with "FPV CAGE V2 FOR 14MM CAM".

• Wheelbase : 127.3mm 
• Total thickness : 5mm (2.5mm each)
• Motor mount : φ9mm, M2 (2pcs. each)
• FC mount : 25.5x25.5mm, M2
• Compatible with whoop style USB connector
• Buit-in battery strap holder (can use up to 15mm width strap)
• Weight : Approx. 16.5g (Carbon only)

Note :  This frame kit has very tight dimensions for the use of large camera mounts; when using the "FPV CAGE V2 FOR 14MM CAM", you must use standoffs of the proper length to prevent propellers interference.

Dimensions : 

Lower Layer : 

Upper Layer : 

This frame kit is designed to mount a nano-sized (14 mm wide) FPV camera and VTX on a simple Toothpick-like frame using appropriate length standoffs. 

• Compatible camera width : 14mm
• VTX mount holes : 20x20mm, 25.5x25.5mm, M2
• Thickness : 2mm
• Weight : Approx. 7.5g (Carbon only)
• Necessary Standoffs : 4 M2x20mm, 2 M2x14mm

Note: The side plates may not be able to be inserted into the top plate or base plate because the thickness varies from lot to lot. If this is the case, please widen the insertion hole by filing. However, even if they are loose, it is not a problem as they are secured by the four standoffs on the camera mount.

Dimensions : 

VTX Size 30x30mm : 

VTX Size 33x33mm : 

VTX Size 34x34mm : 

Two configurations for camera : 

This frame kit is designed for a module type Toothpick frame consisting only of arms, screws and nuts. Each arm, consisting of two bones, is supported not only by two adjacent arms but also by its diagonal arm. Replacing broken arms is not as easy as with a regular frame, but the interlocking of the eight bones eliminates the need for upper and lower plates for fixing. 

As a toothpick frame (2S or above), it does not appear to be disadvantageous in terms of robustness or vibration in the field tests to date. This 3" modular frame is more robust than it looks. 

• Wheelbase : 127.3mm 
• Total thickness : 5mm (2.5mm each)
• Motor mount : φ9mm, M2 (2pcs. each)
• FC mount : 25.5x25.5mm
• Compatible with whoop style USB connector
• Built-in hook for rubber band
• Built-in battery strap holder (can use up to 15mm width strap)
• Weight : Approx. 16g (Carbon only)

Dimensions : 

Lower Layer : 

Upper Layer : 

This frame kit is designed for a module type Toothpick frame consisting only of arms, screws and nuts. Each arm, consisting of two bones, is supported not only by two adjacent arms but also by its diagonal arm. Replacing broken arms is not as easy as with a regular frame, but the interlocking of the eight bones eliminates the need for upper and lower plates for fixing. 

As a toothpick frame (2S or above), it does not appear to be disadvantageous in terms of robustness or vibration in the field tests to date. This 3" modular frame is more robust than it looks. 

• Wheelbase : 127.3mm 
• Total thickness : 5mm (2.5mm each)
• Motor mount : φ9mm, M2 (2pcs. each)
• FC mount : 25.5x25.5mm
• Compatible with whoop style USB connector
• Built-in hook for rubber band
• Weight : Approx. 15g (Carbon only)

Dimensions : 

Lower Layer : 

Upper Layer : 

This frame kit is designed for a module type Toothpick frame with a flat unibody-like form. Consisting only of arms, screws, and nuts. Each two-layered arm is supported not only by two adjacent arms but also by its diagonal arm. Replacing broken arms is not as easy as with a regular frame, but the interlocking of the eight modules eliminates the need for upper and lower plates for fixing. 

• Wheelbase : 127.3mm
• Total thickness : 4mm (2mm each layer)
• Motor mount : φ9mm, M2
• FC mount : 25.5x25.5mm, 20x20mm, 16x16mm
• Compatible with whoop style USB connector
• Built-in battery strap holder (can use up to 10mm width strap)
• Weight : Approx. 14g (Carbon only)

Dimensions : 

Lower Layer : 

Upper Layer : 

This frame kit is designed for 1S (flat) octocopters of 45mm props using AIO FC (F405 or above) and small 1S 4-in-1 ESC (rarely seen these days) to enjoy outdoor 1S digital FPV. This 2mm thick bottom plate is more robust than 1.5mm one. To build this kit, you need to know how to use additional motors in Betaflight. For more detaile, please refer to my article submitted to Rotorbuilds ( https://rotorbuilds.com/build/30046 ) in  which I made 1S octocopter of 40mm props for analog FPV.

• Kit Weight : about 14g (carbon only)
• Necessary Standoffs : 5  M2x18-25mm for Top Plate (depends on the height of VTX); 4 M2x20mm and 1 M2x14mm for Camera Mount

Notes

• 40mm camera cable in HDZero Whoop Lite Bundle is short, which limits camera angles.
• Insertion slots for Camera Mount Side Plate may be too narrow. If this is the case, please widen them by fining.

Bottom plate

• Designed for 1S octocopters of 45mm props
• Optimized for using AIO FC (F405 or above) and small 16x16mm mount 4-in-1 ESC
• Recommend combination is JHEMCU GSF405A and Racerstar Star4
• Motor Mount : φ6.6mm, M1.4 ; φ9mm, M2 (RCinPower 1003)
• Thickness : 2mm
• Weight : about 9.5g

Top Plate

• Designed for mounting VTX and Camera
• Compatible VTX Mount: 25.5x25.5mm, 20x20mm
• Thickness : 1.5mm
• Weight : about 2.5g

Camera Mount Side Plate

• Commpatible camera width : 14mm
• Mount Screw Holes : 2mm, 1.4mm (HDZero Nano Lite Camera)
• Suitable Standoff Height : 20mm
• Thickness : 1.5mm
• Weight : about 0.8g

Note: The 1.5mm-thick CF plate may not be able to be inserted into the kit top plate or camera mount top plate because the thickness varies from lot to lot. If this is the case, please widen the insertion hole by filing. However, even if it is too thin, it will not be a problem as it will be secured by the four standoffs on the camera mount.

Camera Mount Top Plate

• Thickness : 1.5mm
• Weight : about 0.5g
•  

This frame kit is designed for 1S (flat) octocopters of 45mm props using AIO FC (F405 or above) and small 1S 4-in-1 ESC (rarely seen these days) to enjoy outdoor 1S digital FPV. To build this kit, you need to know how to use additional motors in Betaflight. For more detaile, please refer to my article submitted to Rotorbuilds ( https://rotorbuilds.com/build/30046 ) in  which I made 1S octocopter of 40mm props for analog FPV.

• Kit Weight : about 12g (carbon only)
• Necessary Standoffs : 5  M2x18-25mm for Top Plate (depends on the height of VTX); 4 M2x20mm and 1 M2x14mm for Camera Mount

Notes

• 40mm camera cable in HDZero Whoop Lite Bundle is short, which limits camera angles.
• Insertion slots for Camera Mount Side Plate may be too narrow. If this is the case, please widen them by fining.

Bottom plate

• Designed for 1S octocopters of 45mm props
• Optimized for using AIO FC (F405 or above) and small 16x16mm mount 4-in-1 ESC
• Recommend combination is JHEMCU GSF405A and Racerstar Star4
• Motor Mount : φ6.6mm, M1.4 ; φ9mm, M2 (RCinPower 1003)
• Thickness : 1.5mm
• Weight : about 7g

Top Plate

• Designed for mounting VTX and Camera
• Compatible VTX Mount: 25.5x25.5mm, 20x20mm
• Thickness : 1.5mm
• Weight : about 2.5g

Camera Mount Side Plate

• Commpatible camera width : 14mm
• Mount Screw Holes : 2mm, 1.4mm (HDZero Nano Lite Camera)
• Suitable Standoff Height : 20mm
• Thickness : 1.5mm
• Weight : about 0.8g

Note: The 1.5mm-thick CF plate may not be able to be inserted into the kit top plate or camera mount top plate because the thickness varies from lot to lot. If this is the case, please widen the insertion hole by filing. However, even if it is too thin, it will not be a problem as it will be secured by the four standoffs on the camera mount.

Camera Mount Top Plate

• Thickness : 1.5mm
• Weight : about 0.5g

This kit is designed for a modular type frame for toothpick which uses press nuts (BetaFPV clamping nuts) to fix arms. Exchanging an arm is easy by rotating it after removing one screw and loosening center one.

• Wheel Base : 172.5mm
• Arm Thickness : 4mm
• Motor Mount : φ9-12, M2
• Top & Bottom Plate Thickness : 1.5mm
• FC & ESC Mount : 16x16mm, 20x20mm, 25.5x25.5mm, M2
• Compatible with whoop styel USB connector
• Compatible with up to 15mm wide battery straps
• Weight : 18.8g (including five press nuts and five M2x8mm screws)

BetaFPV M2 Clamping Nuts
https://betafpv.com/collections/cable-screw/products/m2-clamping-nuts
https://www.aliexpress.com/item/4001197769908.html

If you do not want to use press nuts, please get parts separately with a normal M2 holes top plate.

This kit is designed for a modular type frame for toothpick which uses press nuts (BetaFPV clamping nuts) to fix arms. Exchanging an arm is easy by rotating it after removing one screw and loosening center one.

• Wheel Base : 155.6mm
• Arm Thickness : 3mm
• Motor Mount : φ9-12, M2
• Top & Bottom Plate Thickness : 1.5mm
• FC & ESC Mount : 16x16mm, 20x20mm, 25.5x25.5mm, M2
• Compatible with whoop styel USB connector
• Compatible with up to 15mm wide battery straps
• Weight : 13.5g (including five press nuts and five M2x6mm screws)

BetaFPV M2 Clamping Nuts
https://betafpv.com/collections/cable-screw/products/m2-clamping-nuts
https://www.aliexpress.com/item/4001197769908.html

If you do not want to use press nuts, please get parts separately with a normal M2 holes top plate.

• Optimized for Diatone F1 Camera Protector and 20mm rear standoffs,  M2
• Camera Mount Width : 14mm
• VTX Mount : 16x16mm, 20x20mm, M2
• Main Frame Mount : 25.5x25.5mm, M2, BetaFPV Clamping Nuts
• Thickness : 1.5mm
• Weight : 9.7g (including hardwares)

Diatone F1 Camera Protector
https://www.aliexpress.com/item/1005002833101286.html

BetaFPV M2 Clamping Nuts
https://betafpv.com/collections/cable-screw/products/m2-clamping-nuts
https://www.aliexpress.com/item/4001197769908.html

• Optimized for Diatone MXC 25/L3/L4/TAYCAN  C25 Camera Protector and 23mm rear standoffs,  M2
• Camera Mount Width : 19mm
• VTX Mount : 16x16mm, 20x20mm, M2
• Main Frame Mount : 25.5x25.5mm, M2, BetaFPV Clamping Nuts
• Thickness : 1.5mm
• Weight : 11.5g (including hardwares)

Diatone MXC 25/L3/L4/TAYCAN  C25 Camera Protector
https://www.aliexpress.com/item/1005001307694764.html

BetaFPV M2 Clamping Nuts
https://betafpv.com/collections/cable-screw/products/m2-clamping-nuts
https://www.aliexpress.com/item/4001197769908.html

• Optimized for Diatone MXC 25/L3/L4/TAYCAN  C25 Camera Protector and 23mm rear standoffs,  M2
• Camera Mount Width : 20mm
• VTX Mount : 16x16mm, 20x20mm, M2
• Main Frame Mount : 25.5x25.5mm, M2, BetaFPV Clamping Nuts
• Thickness : 1.5mm
• Weight : 11.6g (including hardwares)

Diatone MXC 25/L3/L4/TAYCAN  C25 Camera Protector
https://www.aliexpress.com/item/1005001307694764.html

BetaFPV M2 Clamping Nuts
https://betafpv.com/collections/cable-screw/products/m2-clamping-nuts
https://www.aliexpress.com/item/4001197769908.html

This kit is designed for a 3" toothpick style X8 octocopter. 

TuneRC Poly F405 2S-4S AIO FC has soldering pads dedicated for M5-M8. Now, anyone can build a toothpick style 3" X8 by adding a 4-in-1 ESC and four motors with this kit.  Even if your AIO FC (F405 or above) does not have soldering pads dedicated for M5-M8, you  can still make an X8 by making resourse remapping LED_STRIP, unused UARTS, or unused SCL (I2C) to M5-M8, and making those pins enable timer and DMA (for DSHOT).

If you want to mount an additional 4-in-1 ESC under the main plate, the Minimal Bottom Plate 1.5mm is reccomended for protecting it.

• FC and ESC Mount : 16x16mm, 20x20mm, 25.5x25.5mm, M2
• Wheel Base : 140mm
• Thickness : Main Plate 3mm, Motor Mount 2.5mm
• Weight : About 16g

As for compatibility with the FPV Cage series, this frame kit with 3" props is compatible only with the FPV Cage for 14mm Cam. 

This kit consists of the SimplePick-EX 3mm version and four of Arm-Splitter (2.5mm). If you have an AIO FC with F405 or above, it is easy to build an octocopter even if it does not have enough dedicated motor pads. For that purpose, you only need to make resource remapping the LED_Strip, unused UARTs, or unused SCL (I2C) to M5-M8, and make those pins enable timer and DMA (for DSHOT). There are 1-2S AIO FCs with F405 by JHEMCU and Flywoo, it is also possible to build a 1S octocopter.

If you want to mount an additional 4-in-1 ESC under the main plate, the Minimal Bottom Plate 1.5mm is reccomended for protecting it.

• FC & ESC Mount : 16x16mm, 20x20mm, 25.5x25.5mm, M2
• Compatible with the Whoop-type USB connector
• Motor Mount : φ9mm, M2
• Weight : About 16g

The most AIO FC (F411, F405, ...) can controle six motors if you make resource remapping the LED_STRIP, unused UARTs, or unused SCL (I2C) to M5 and M6, and make those pins enable timer and DMA (for DSHOT). So, I mada a kit which consists of a usual toothpick frame and an additional arm and spacers whch extend a quad toothpick to a hexacopter.

An addional mid arm has 130mm Motor-to-Motor length, which is enough for 3" hexacopter.  Using motor mount spacers (5mm), you can align the directions of all propellers of thickness less than 7.5mm. For a successfull build, two additional motors should have diameter less than 18mm, othersize 3" propellers on the front and the rear motors hit the mid motors.

If you want to mount additional ESCs under the main frame, the Minimal Bottom Plate 1.5mm is reccomended for protecting them.

• FC and ESC mount : 16x16mm, 20x20mm, 25.5x25.5mm, M2
• Compatible with the whoop-type USB connector
• Motor Mount : φ9mm M2
• Mid Arm Legth: 130mm Motor-to-Motor
• Motor Mount Spacer Thickness: 5mm
• Compatible Motor Bell Diameter: Less than 18mm
• Weight : About 12g

The front standoff mounting holes are suitable for using "Diatone ROMA F1 Camera Metal Protector" for a Nano size camera. For that purpose, the rear standoff height should be 20mm.

https://www.diatone.us/collections/roma-acc/products/diatone-roma?variant=39321176637527

The following picture shows my 3" light weight build of the 2.5mm bottom-plate version with Diatone ROMA F1 Camera Protector.

This is the Bat-Hex kit with 3mm Bottom Plate (carbon only).

• Please note that the mid arms and braces may be not robust enouph for had crash. 
• FC, ESC, VTX mounting holes: 25.5x25.5mm(Front only), 20x20mm, 16x16 (front and rear), M2
• Motor mounting holes: 9x9mm, M2
• Standoff mounting holes spacing: Front=18mm, Rear=14mm; M2
• Prop size: 2"(flat), 2.5"-3"(front and rear props should be pusher)
• Thickness: bottom=3mm, top=1.5mm
• Weight: About 24g
• Betaflight Motors Mixer: HEX X

The front standoff mounting holes are suitable for using "Diatone ROMA F1 Camera Metal Protector" for a Nano size camera. For that purpose, the rear standoff height should be 20mm.

https://www.diatone.us/collections/roma-acc/products/diatone-roma?variant=39321176637527

The following picture shows my 3" light weight build with Diatone ROMA F1 Camera Protector. This frame is a prototype and is not the same as the product.

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This is the Bat-Hex kit with 2.5mm Bottom Plate (carbon only).

• Please note that the mid arms and braces may be not robust enouph for had crash. 
• FC, ESC, VTX mounting holes: 25.5x25.5mm(Front only), 20x20mm, 16x16 (front and rear), M2
• Motor mounting holes: 9x9mm, M2
• Standoff mounting holes spacing: Front=18mm, Rear=14mm; M2
• Prop size: 2"(flat), 2.5"-3"(front and rear props should be pusher)
• Thickness: bottom=2.5mm, top=1.5mm
• Weight: About 21g
• Betaflight Motors Mixer: HEX X

The front standoff mounting holes are suitable for using "Diatone ROMA F1 Camera Metal Protector" for a Nano size camera. For that purpose, the rear standoff height should be 20mm.

https://www.diatone.us/collections/roma-acc/products/diatone-roma?variant=39321176637527

The following picture shows my 3" light weight build with Diatone ROMA F1 Camera Protector. This frame is a prototype and is not the same as the product.

The front standoff mounting holes are suitable for using "Diatone ROMA F1 Camera Metal Protector" for a Nano size camera. For that purpose, the rear standoff height should be 20mm.

https://www.diatone.us/collections/roma-acc/products/diatone-roma?variant=39321176637527

The following picture shows my 3" light weight build with Diatone ROMA F1 Camera Protector.