K&F Concept Lens Mount Adapter Contax Yashica C/Y Lens to Canon EOS EF Adapter, for Canon EOS 1D, 1DS, Mark II, III, IV, 5D, Mark II, 7D, 30D, 40D, 50D, 60D, 70D, Digital Rebel T2i, T3, T3i, T4i Allows Contax Yashica C/Y Lens to fit on Canon EOS EF mount camera body. There are no electrical contacts in the adapter ring,exposure and focus has to be adjusted manually. Smooth surface for effortless mount, fine made to be light weight and strong. Made of brass and aluminum (not plastic), with precise design and high technology. Please note: Infinity focus positionthe position of the infinity mark of the telephoto lens or super telephoto lens is shifted slightly to the positive side to enable focus adjustment even when focus shift is caused due to temperature changes.The shift range is denoted by an L-shaped line, Be sure to check the focus through the viewfinder even when you shoot at infinity.