Description Product Details Warranty Information Proof Vista-Crystal : Eco-friendly frames from Proof Eyewear. Handcrafted from cotton based acetate. BPA free. Water and sweat-resistant. Quote on inside of temple: "See the good" With each frame purchased, five trees are planted. Frame Material: Cotton based acetate with spring hinges. Fully biodegradable. Fit: Medium 50 19 140 39.5 Comes with: Companion Case, Cleaning Cloth, 1oz. Eyeglass Cleaner Free Shipping (USA) Frame Size: Medium (49-52mm) Bridge Width: 19mm Temple Length: 140mm Color: Crystal Shape: Square Material: Bio-Acetate Style: Full-Rim Spring Hinge: Yes newOptions: true 30-Day No-Hassle Guarantee