The Adapter Tube for Canon G7 & G9 is a 58mm adapter tube specifically made to mount filters, lenses and other accessories onto your camera. The adapter screws directly onto the lens barrel ring and is designed to move with the lens while zooming in and out. This provides filter coverage throughout the zoom range and prevents vignette at the wide-angle end of the zoom. It is dedicated for use with the Canon G7/G9 and will support any kind of 58mm filter, lens hood, or conversion lens.