Prolonged exposure to blue light from computer screens and digital devices causes symptoms of eye strain, fatigue, migraines and dry eyes. Our computer readers effectively filter 60% of blue light to reduce damage from harmful rays. Features: Anti-Reflective coating to prevent glare Blue light blocking lenses that block 60% of blue light Aspheric lenses to prevent distortion Anti-scratch coating Spring hinges to maximize comfort Care instructions: Clean lenses with eyeglass cleaner and a clean microfiber cloth. Store in case when not in use. Lens Width: 48mm Lens Height: 36mm Bridge Distance: 13mm Arm Length: 140mm