This is one of the Pro-series lens mount adapter made with precision and pristine award standard. As all Pro-series adapters, these adapters have been specially crafted to endure professional lenses. No "play" between lens and Camera. With unique styling, the lens mount adapter maintains/enhances professional appearance. This lens mount adapter allows Bronica SQ series lens to fit on Canon EOS camera body. Does NOT work on Canon EOS 5D Mark III.