Like the MFT format, the L Mount Alliance offers users the opportunity to use one mount across, in this instance, three camera brands. Deigned by Leica, the new mount lenses can be used on new Panasonic models, notably their S1 and S1R cameras, a promised SIGMA camera with their own branded line-up of lenses, and of course Leica interchangeable lens cameras. The L mount measures 51.6mm in diameter, which can be used on both full-frame and APS-C format cameras, and its short flange-to-sensor distance allows optical designers to produce more compact lenses. There is also a standardized array of 12 electronic contacts, providing enhanced communication between camera and lens as well as ease of loading firmware updates.