Pack of 50 5×7 Picture Mats for 4×6 Photos. These mats are made of acid-free, and pre-cut for immediate use. The opening size is 3.5″ x 5.5″ for 4×6 photo prints. Color: white. 4-ply (~1.4mm or 1/16 inch) mats, both white core and bevel cut. Each items is professional packed and shipped to ensure a safe arrival of your purchase. Set Of 50 White 5X7 Whitecore Picture Frame Mats High Quality Mats Opening Size Is 3.5 X 5.5 Inches For 4X6 Pictures Mats Are Beveled Cut And Are 4-Ply Thick 1.4 Mm Or 1 16 Inch All Acid Free, Perfect From Hobbies To Art Gallery Exhibits.