1) M42 Lens to EOS Lens Mount Stepping Ring 2) It is easy to install, remove and use 3) It is durable and reliable for long-term use 4) It is made of metal 5) A useful thing to achieve optimal shooting effect 6) With lock pin and stop screw. 7) Please note Although the lens will fit physically, automatic diaphragm, auto-focusing, or any other functions will not operate correctly while using this adapter.

http://olla.gr/m42-lens-to-eos-lens-mount-stepping-ring-black/