Description : 100% Brand New & High Quality Make M42 mount lenses (Zeiss, Pentax, Praktica, Mamiya, Zenit) can be used on Canon EOS cameras. apart from pentax takumar, the inner diameter is: 36mm. Allows focusing to infinity. Made of brass with chrome coating in silver finish The view finder also indicates the focused area with a spot as well. Auto focus (AF) is not available. Stop-down metering is used. Spot metering mode does not work properly. Although it is possible to use the A (aperture-priority AE) mode in auto exposure, the aperture display is not available. In the P (Program AE), or S (Shutter speed-priority AE) mode, the shutter releases, but the auto exposure control does not work. The distance scale on the lens might not indicate the actual distance. Please installing \/ uninstalling the adapter after turning off the camera. The EOS autofocusing system doesn't support as less as F5.6. Before your capturing you have to focusing with MAX aperture and stop down to capturing. Compatible with: All CANON EOS camera bodies,such as 550D, 450D, 400D,350D, 300D, 40D, 30D, 20D, 10D,5D ,D60, D30, 1Ds Mark II, 1Ds mark III, Rebel etc, except EOS 30, 30V & 33V. Package Included : 1 x M42 to EOS Adapter Ring