Mini anti-theft folding lock is composed of zinc alloy and ABS. The inner layer of zinc alloy lock body is stronger than ordinary lock body; the outer layer of nylon plastic wraps, does not scratch the frame. It has very strong anti-cut, anti-drill keyhole and anti-smash lock body functions. More importantly, it is very small and portable, and does not add burden to riding. You can mount it on the frame, under the saddle tube or in a bike bag.