Crews will be happy to let you know that these Tomahawk glasses are very safe, durable, protective, comfortable, and stylish. They feature a fully-adjustable, five-position ratchet-action temples, and a stylish wrap-around design with a one-piece polycarbonate lens and integral sideshields. These glasses also have a lightweight frame which provides added comfort and balance. Let's not stop there because these lenses also filter out 99.9% of UV radiation and are treated with Duramass scratch-resistant coating. All these great features are rolled into one to meet ANSI Z87+ 2003 and CSA Z94.3 standards.