The Aquatica Zoom Gear for Panasonic LUMIX G 7-14mm f/4.0 ASPH Lens in Lens Port is specially designed to mount on the zoom ring of the Panasonic LUMIX G and enables zoom control when the lens is inside a port. It connects to a compatible underwater housing's zoom control knob. Manually rotate the zoom control knob to move the zoom back and forth while shooting.