A zipper is a fastener composed of chain straps, sliders and functional accessories. The chain belt of nylon zipper is composed of cloth belt, fastener element and suture, and the chain belt of metal zipper and plastic-steel zipper is composed of cloth belt and fastener element with central thread. The elements of the metal zipper and the plastic-steel zipper are symmetrically distributed relative to the cloth belt, so the bearing capacity is relatively uniform, while the chain elements of the nylon zipper are asymmetrically distributed relative to the cloth belt.

In order to realize the different forms and functions of the zipper, choose different accessories to assemble to form an open-end pull-select or a closed-end zipper. Different functional accessories include top and bottom stops, cannula, sockets, reinforcing tape, etc.

The main function of the zipper is that the chain belt can be separated and closed, and the closed chain belt can still maintain the stability of the engagement after a certain external force is applied. The basic principle is that the elements on the chain belt are designed as a pair of concave-convex structures. When engaged, under the guidance of external force, the elements will enter each other's space, and the concave-convex structure makes the teeth peaks of the elements. It forms a state of mutual locking with the tooth valley. This locking relationship is stable, so the locked fastener elements will not automatically disengage.