This port is designed specifically for the canon 17 85mm f4 56 ef s is usm lens zoom is provided via a built in control and gear afmf and image stabilization switches cannot be changed while installed in the housing auto focus only this lens requires the addition of a 4 close up lens to focus properly behind a dome underwater close up lens not included ikelite acrylic domes are injection molded specifically for underwater photography and represent the finest optics in the industry