Self-adhesive bags are plastic packaging bags with a self-adhesive layer (self-adhesive) on the back. They are usually made of PE (polyethylene) or PP (polypropylene) and have the characteristics of being waterproof, dustproof and having strong adhesion. It is mainly used in the logistics and express delivery industries. It is pasted on the surface of cartons or packages to load shipping orders, invoices, waybills or other accompanying documents, facilitating counting and information transmission.