● These inexpensive, reusable mat frames will dress up any exhibit or offer a colorful way to display student artwork 12 in. ● x 18 in. ● Black on both sides. ● 4 ply. ● O.D. ● 16-1/2 in. ● x 22-1/2 in., I.D. ● 11-1/2 in. ● x 16-3/4 in. ● Package of 12.