In BDSM terms, a zipper is a string of clothespins or other clips, held together loosely by a cord or light chain.
The skin is clipped in the clips for a short time, then the cord is pulled causing the clips to be pulled off the skin one by one in sequence causing a "zip" sound, and a unique sensation. Zippers come in many sizes and varied numbers of clips. They are a very popular home-made BDSM toy. A Zipper can also be created with temporary piercing needles.