The Nikon WP-ZG1000 Zoom Gear Sleeve for WP-N1 Waterproof Housing
works with the zoom gear to enable you to operate the zoom function on
the 10-30mm VR lens while shooting with your Nikon 1 J1 or J2 digital
camera inside the WP-N1 Waterproof Housing. The sleeve serves as a
replacement or spare for the one that came with your housing.