ThinOptics Keychain Case and Reading Glasses - +2.5, Black - THO-24203. Designed to bend without breaking. Ultra-flexible titanium alloy bridge made from Nitinol (10x more elastic than spring steel). Independent-suspension nose pads ensure a universally comfortable and stable fit. Styled shatter-proof polycarbonate frames. Handy keychain case keeps glasses safe so you never lose them.Our new Keychain Case makes finding your reading glasses even simpler. Now your glasses will go where you go and will be there whenever you need them. The unique design allows ThinOPTICS to fold down and slide into the case to keep them safe and always within reach.