Orion 05224 T-ring for Canon EOS Camera (Black) Ring attaches securely to Canon EOS DSLR or SLR camera body and provides a T-thread interface Couples Canon EOS camera body to standard T-thread found on many camera adapters used for astrophotography Securely fits Canon EOS 35mm DSLR and SLR cameras via bayonet-style attachment Made of rugged anodized aluminum