 Leica do not recommend that 1 cam lenses be used on R8 or R9 cameras because of possible damage to the cameras' ROM contacts.1 cam lenses may be fitted with later 2 cams, 3 cams, or R cam + ROM contacts (replacing the sloped cams).2 cam lenses have two sloped cams for the Leicaflex SL and SL2 with TTL metering and are fully compatible with the original Leicaflex.