TGL MAILING Board Back Envelopes TGL MAILING board backed “Please do not bend” envelopes are made from 100% recycled material consisting of a 1000 micron solid cardboard backing paired with 120gsm kraft paper front. These heavy duty manilla hard backed envelopes are designed to offer protection against bumps and scrapes in the post ensuring your important documents remain flat, crease-free & safe. They are the ideal choice for mailing legal documents, certificates, contracts, photos, artwork, catalogues, blueprints & more. These do not bend envelopes come with a peel and seal strip offering a quick & secure seal resulting in increased packing speed as you won't need any additional tape or glue to seal. Their light yet robust structure helps you keep your shipping weight in check without compromising on protection. The smooth kraft finish on the front will allow you to either handwrite addresses directly or attach sticky address labels for a more professional look