Pack of 10 16x20 White/Black Double Mats Mattes with White Core Bevel Cut for 11x14 Photo + Backing + Bags Pack of 10 16x20 White/Black Double Mats Mattes with White Core Bevel Cut for 11x14 Photo + Backing + Bags This item comes with 10 16x20 single mats, 10 backing, and 10 bags The opening size is 10.5"x13.5" for 11x14 print. The mats are beveled cut with white core and 4-ply thick (about 1.4 mm or 1/16 inch). The re-sealable adhesive strip of the clear bag is below the opening of the bag instead of on the flap.