EF lens mount

The EF lens mount allows all the Canon EF lenses to be used on any of the Canon EOS line of cameras made by Canon Inc. Unlike the EF's breech-lock predecessor, the FD mount, the EF mount uses a bayonet-style mount. EF stands for "Electro-Focus": automatic focusing on EF lenses is handled by a dedicated electric motor built into the lens. All communication between camera and lens takes place through electrical contacts; there are no mechanical levers or plungers.
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