Smith Optics Interlock Trace Sunglasses plastic frame gradient lens Non-Polarized Lens width: 62 millimeters Bridge: 20 millimeters Arm: 120 millimeters Stylish sunglass with patented interchangeable lens system Arms swivel open to release lenses and swivel back to lock them Grilamid TR-90 frame with hydrophilic Megol on nose and temple pads TLT carbonic lens technology provides distortion-free clarity Available in medium fit; backed by lifetime warranty