Mat Board Center, Crescent Pack of 50 sets 5x7 MIXED COLORS Cream Core Picture Mats Mattes Matting for 4x6 Photo + Backing + Bags Mat Board Center, Set of 50 High Quality pieces of Crescent 5x7 Cream Core Picture Mats for 4x6 Photo with backing boards and bags The mat opening size is 3.5"x5.5" for 4x6 print. Color: Mixed color The clear bag's re-sealable adhesive strip is below the opening of the bag instead of on the flap. This item comes with the 50 pre-cut mats, 50 backing boards and 50 clear bags. The mats are beveled cut with cream core and 4-ply thick (about 1.4 mm or 1/16 inch), The backing is white on both side.