The stack mounting is compatible with 20 20MM and 30.5 30.5MM, which can cover all types of stacks on the market. The VTX mounting is compatible with the movable M2 (20 20MM) and M3 (30.5 30.5MM), which can cover all kinds of VTX: Analog, Vista, HD Link, DJI O3, and DJI AIR UNIT.
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