THE HOMEHOBBY BY 3L MOUNTING CORNERS REGULAR Our clear, self-adhesive Mounting Corners are traditionally-styled full corner design. Intended for items up to 51 x 61cm, use for framing on posters, photos, artwork, diplomas, documents, certificates and even scrapbooks and crafts. Mounting Corners are perfect for photographers, libraries, museums and other archival use. Transparent polypropylene is acid free, non-yellowing, and meets archival and conservation requirements and preservation standards. It is PAT (Photo Activity Test) tested. The acrylic based permanent adhesive is pressure sensitive, never comes in contact with the artwork, and will not bleed or crawl. To use, simply remove from the liner paper, position onto corner of art, and press onto the backing media.