Canon EF 1200mm 5.6L USM is the company’s most powerful supertelephoto lens. In terms of focal length and maximum aperture, it is the World’s largest interchangeable SLR AF lens. The lens consists of 13 elements in 10 groups with protective glass and drop-in filters. Through the advanced inner focusing system with USM and Extender EF 1.4x or 2x, a focal length of 1700mm f/8 or 2400mm f/11 can be acquired. Other features include 2°05' diagonal angle of visualization, 8 diaphragm blades, built-in Lens hood with a hard case and 32 as minimum aperture.