50 set of 11x14 Black Photo Mats for 8x12 + backing + bags: Home & Kitchen. Buy 50 set of 11x14 Black Photo Mats for 8x12 + backing + bags: Storage & Presentation Materials - ✓ FREE DELIVERY possible on eligible purchases. 50 set of 11x14 Black Photo Mats for 8x12 + backing + bags 。 This item comes with 50 single mats, 50 backing, and 50 bags. 。 The opening size is 7.5"x11.5" for 8x12 print with a bevel cut. 。 The mats are beveled cut with white core and 4-ply thick (about 1.4 mm or 1/16 inch). 。 Our acid-free whitecore matboards are a 4-ply papermat that provide the aesthetic and design benefits of a bright white bevel. It can be used for matting photos, art, and needlepoint. Also great for crafts, backboards, signs, children's projects, and school projects. 。 。 。