... available in all photographic sizes. Properties:Glassine envelopes are made from pure pine wood cellulose which ... acid free and does not contain chemical softeners.Envelopes do not have an adhesive seal, but ... flap folded over to ensure seeds stay in packet.Available Format: Open End Center Seam Open ... the safe protection of stamps,blocks,sheetlets,envelopes,Fdc's,postcards,telephone cards,bank notes, ...