Pack of 10 16x20 BLACK Picture Mats with White Core Bevel Cut for 11x14 Pictures Pack of 10 16x20 BLACK Picture Mats with White Core Bevel Cut for 11x14 Pictures This item comes with 10 16x20 single mats Inside (opening) Size: 10.5x13.5 (bevel cut), Color is BLACK White core and 4-ply thick (about 1.4 mm or 1/16 inch) THIS ITEM DOESN'T INCLUDE BACKING BOARD.