Golden State Art, 8x20 Matted Black Wood 4-Opening for 4" x 6" Collage Picture Frame IMPORTANT NOTES: IT COMES WITH REAL GLASS. Not Acrylic! This picture frame comes with single mat with 4 openings for 4 4x6 pictures Picture size: Four 4x6-inch (with mat, white color, Opening size: 3.5x5.5) Bevel cut mat with white core and 4-ply thick (about 1.4 mm or 1/16 inch). 1'' wide and 0.75'' thick molding, Hangs vertically or horizontally