500 A4 318mm x 235mm Self Adhesive Printed Documents Enclosed Wallets Manufactured from Printed Polythene, Internal Dimensions 318mm (width) x 235mm (height). A4 / C4 Document Size. Strong Adhesive Backing. These Documents Enclosed Labels are designed to attach invoices and dispatch notices onto packages and cartons. Manufactured from strong Polythene and featuring a peel able backing with strong adhesive that ensures that any enclosed documents remain with the attached package through the postal system and are protected from dirt, dust and moisture.