Master Laminating pouches use a proprietary blend of several different types of plastic to provide strength and clarity with a modest amount of UV protection. These pouches are an excellent choice for a variety of documents, including normal paper and thicker materials such as photo paper up to 5 mil thick. The pouches are ideal for laminating standard sheets of paper and do not require the use of a carrier or cover sheet. Documents laminated with thses pouches are thick, stiff & durable .They produce a crystal clear finish, are not tinted, and are great for photos, school projects, presentation documents, and documents that need preserving. The corners are rounded for design and safety. The lengthwise seam keeps the laminate in place and helps reduce air bubbles.