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The Roxy Grasshopper sunglasses are head turners with oversized style and unbeatable protection from the sun. Frames are constructed from cellulose propionate (thermoplastic), which is lightweight and hypoallergenic. Black tortoise frames feature CR-39 lenses providing 100% UVA, UVB and UVC protection; 16% visible light transmission (VLT). Shiny black frames feature lightweight and virtually shatterproof, polycarbonate lenses that are 20 times more impact resistant than glass and one-third the weight; 8% VLT. Distortion-free and shatterproof lenses provide a 6 base curve coverage for everyday wear.