50 16x20 White Mats Mattes Matting for 11x14 + backing + bag 50 16x20 White Mats Mattes Matting for 11x14 + backing + bag This item comes with 50 single mats, 50 backing, and 50 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).