This Body Cap for Canon Camera from OP/TECH USA protects the internal parts of a Canon camera body (which has an EF or EF-S mount) when there's no lens on it. The cap is made from a durable polycarbonate material to withstand the rigors of daily use. There's also a thermoplastic rubber seal molded as an integral part of the cap which effectively grips to the camera body and forms a friction fit to lock out dust and moisture.