General supermarkets or hardware stores can buy heat-shrinkable films. Heat shrinkable film is widely used, and it is usually sold in Shang Dynasty or hardware store. The materials used for heat shrinkable films are mainly various thermoplastic films. At first, it was mainly made of PVC shrink film. With the continuous development of market demand, PVC shrink films gradually decrease, while various multilayer shrink films such as PE, PP, PET, OPP, PVDC and POF develop rapidly and become the mainstream of the market.