Calvin Klein Ck Rx Eyeglasses Frames 5173 604 49x18 Bordeaux Flexon plastic frame plastic lens non-polarized Lens width: 49 Arm: 135 millimeters FLEXON Flexon is 10 times springier than spring steel and 25% lighter than conventional metals Made from a titanium alloy Flexon frames are more resilient, weigh less and are a lot more comfortable to wear than conventional metal frames Unlike other metals, Flexon can remember and return to its original set shape