Finished to exacting specifications and machine polished with high velocity micro particulates, the engineering behind Gunnar Phenom computer glasses are only outdone by one thing... its artistic style. Aluminum-magnesium frame construction generates proper strength and optical stability through a hybrid lightweight metal alloy. Micro-engineered lenslocks add both flexibility and flair while securely retaining lenses without undue stress or distortion of the optics. Soft thermoplastic rubber tipped temples grip lightly to ensure proper location of the optics without slippage. Hidden spring hinges flex to ergonomcally fit a wide variety of head and face shapes.