FPV camera sizes (nano 14, micro 19, mini 22, full 28 mm) and DJI O3 / O4 air unit dimensions — dimension sheet
Source: Xem Studio, https://xemstudio.com/objects/fpv-cameras-and-air-units/  (CC BY 4.0)
Basis: DJI specs; camera makers' pages via dealers; mount holes for O4 Pro from a maker review
Catalog version: 2026-10-20

Sizes: see table below
- Camera body classes by front width: nano 14 × 14 (Caddx Ant), micro 19 × 19 (Caddx Ratel 2, 19 × 19 × 20), mini 22 × 22, full 28 × 28 (mini cameras often ship with a 28 mm adapter).
- Side M2 screw positions are not published for these cameras, so the cages have slots instead of holes.
- DJI O4 Air Unit Pro: camera 25.55 × 20 × 23.3, VTX 33.5 × 33.5 × 13 (32 g with camera); VTX M2 threads on 20 × 20 and 25.5 × 25.5, camera 2 × M2 16 apart (maker review). DJI O4 (lite): camera 13.44 × 12.36 × 16.5, VTX 30 × 30 × 6.
- DJI O3 Air Unit: VTX 32.5 × 30.5 × 14.5, camera 21.2 × 20 × 19.5, 25.5 × 25.5 mount. Planes and cars: use the 19 or 22 cage on a tilt plate; vibration-isolate with TPU.

unit  camera_mm  vtx_mm  mount  weight_g
nano class (Caddx Ant)  14 × 14  None  None  2
micro class (Caddx Ratel 2)  19 × 19 × 20  None  None  5.9
mini class (Foxeer Predator 5 Mini)  22 × 22  None  28 mm adapter  8.7
DJI O4 Air Unit Pro  25.55 × 20 × 23.3  33.5 × 33.5 × 13  20 × 20 and 25.5 × 25.5 M2  32
DJI O4 Air Unit  13.44 × 12.36 × 16.5  30 × 30 × 6  None  8.2
DJI O3 Air Unit  21.2 × 20 × 19.5  32.5 × 30.5 × 14.5  25.5 × 25.5  36.4
ELRS nano receiver (BetaFPV)  None  12 × 19  None  0.7
VTX (Rush Tank Ultimate Mini)  None  28 × 28 × 3.3  20 × 20  4.46

Files elsewhere (not hosted by Xem Studio; license as stated by the publisher):
- DJI: O4 Air Unit specs — web — Publisher's page; dimensions are facts — https://dji.com/o4-air-unit/specs
- Unmanned Tech blog (maker review): DJI O4 technology review — web — Publisher's page; dimensions are facts — https://blog.unmanned.tech/dji-o4-fpv-technology-review/
- GetFPV (DJI spec): DJI O3 Air Unit — web — Publisher's page; dimensions are facts — https://www.getfpv.com/dji-o3-air-unit.html
- ReadyMadeRC (Caddx spec): Caddx Ant — web — Publisher's page; dimensions are facts — https://www.readymaderc.com/products/details/caddx-ant-fpc-camera
- Unmanned Tech (Caddx spec): Caddx Ratel 2 — web — Publisher's page; dimensions are facts — https://www.unmannedtechshop.co.uk/products/caddx-ratel-2-1200tvl-fpv-camera-2-1mm
- Rotorama (Foxeer spec): Foxeer Predator 5 Mini — web — Publisher's page; dimensions are facts — https://www.rotorama.com/kamery/foxeer-predator-v5-mini
- BetaFPV: ELRS Nano receiver — web — Publisher's page; dimensions are facts — https://betafpv.com/collections/expresslrs-series/products/elrs-nano-receiver

Free files (CC BY 4.0, Xem Studio; STEP + STL, 5 parts): https://xemstudio.com/files/hardware/fpv-cameras-and-air-units/index.json
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