This AquaTech EDGE Sony FX3 and FX30 Conversion Kit lets you use your camera in an Aquatech EDGE Sport housing originally designed for a different model. It contains a dedicated backplate with camera controls, a camera plate, and a dedicated cable release, all compatible with the FX3 and FX30.
The great advantage of using a conversion kit is that you can cross between camera models or manufacturers without needing to purchase a new water housing if you upgrade your camera or would like to use two different cameras in the water for different reasons.