ThinOptics™ reading glasses are made from thermo-injection molded optical grade polycarbonate, which is shatter proof and frequently used in safety and ballistic (bullet proof) eyewear. The bridge is made from Nitinol, which is 10x more elastic than spring steel. The Nitinol bridge is encased in medical grade silicon tubing, and anchored in the injection molded polycarbonate frame. Still not convinced? Check out how we torture test ThinOptics in Sonoma, California in this video.