Pack of 25 pre-cut mixed color 8x10 photo mats matte with white core, 4-ply thick (1/16in - 1.4mm). The backing is white on both side. Acid free 8x10 pre-cut picture mat board kit for 5x7-inch photos. Add additional decoration for your pictures or prints, personalize your artwork and decorate your home. Photo Mat Opening Size: 4.5" x 6.5" with 45° white core bevel cut. This item comes with 25 pcs acid free mats, 25 pcs clear bags, 25 pcs backing boards. The re-sealable adhesive strip of the clear bag is below the opening of the bag instead of on the flap. Perfect for framing all your photographs or prints! With a variety to choose from, coordinating a picture and frame has never been easier! This item comes with 25 pre-cut mats, 25 backing boards and 25 clear bags. The opening size is 4.5"x6.5" for 5x7 print. The mats are beveled cut. The backing is also 4-ply. Our acid-free white core mat boards are a 4-ply paper mat 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.