This ring has been designed around the Canon CN-E 14mm T3.1 wide-angle prime lens. The clamp-on ring allows the Lightweight Matte Boxes LMB-4A and LMB-6 to cover up to the full frame 24x36mm sensor size (FF35) of EF mounted cameras such as Canon 1Dc, 1D and 5D MkIII.

For use with Cooke 18-100 mm + 25 -250 mm Cinetal + ARRI VPs