... .Wholesale Custom printed a4 mailing bags 3 Plastic courier mailing envelope. 4.LDPE / HDPE Products: Custom printed a4 self adhesive plastic ... color, printing on outside, 0.035-0.12mm thickness, good security feature, eco-friendly products.FunctionStrong film with strong side sealing ... and strong tape. This kind of bag is used for courier, express, and mail services.StylePoly mail bag, Lightweight for ...