Mount this Focus Gear from Fantasea Line onto your Sony E 30mm f/3.5 Macro Lens before the lens is placed inside the FML Flat Port 34. This port is compatible with Fantasea underwater camera housings that have FML mounts, including the FA6500 enclosure for Sony's Alpha a6500 and a6300 models. The gear connects to the housing's lens dial, which can be turned for smooth, seamless operation of the 30mm's focus control.