Mount the Sony FX3 XLR handle onto your Sony a7 IV or a7S III mirrorless camera when using a cage with this Cage Adapter Plate from SmallRig. The plate installs on top of select SmallRig cages designed for the a7 IV or a7S III using the captive screws. The FX3 XLR handle mounts onto the camera's top shoe mount, and the plate ensures that the handle is secure and has no play.