Heavy duty board back envelopes in white and manilla, made using 1000 micron backing board and a heavyweight face paper to ensure protection when posting bendable items.. - Box Quantity: 125.. - Pallet Quantity: 8000.. Features. Self-adhesive closure. Yes. Media weight. 120 g/m². Window. No. Product colour. Cream. Material. Paper. Weight & dimensions. Length. 267 mm. Width. 318 mm. General. Product family. Purely. Product series. Packaging