The Merlins frame is extra light weight at less than 1 oz. and completely disappears with all day wear in the field, or on the shooting ground, causing no bridge pain. It features a large lens designed to ride higher on the face with no visual interruption in the sight picture. The lenses are easily interchangeable, and with our patented lens anchor technology no tools are required. A bolt is threaded into the lens and hooks onto two places on the frame. The Merlin ships with the Crystal Saddle nose piece.