A plastic film that is used to wrap something (very often a product for sale).
When heat is applied to it, it shrinks to conform to the product inside. This is often done to hold food onto a tray in food packaging, or when done to another container (such as a medicinebox, cd case, or video gamebox) to be tamper-evident for safety or prevent theft. It is also used on books and manga either to prevent minors from viewing adult content or to prevent shoppers from reading in a store without purchasing.
