16x25 Matting for Picture Frame Maroon with Cream Core and 12x21 Opening Size (B038MAT) MAT SIZE: This matting fits a 16x25 frame. (frame not included) OPENING SIZE: This mat fits a 12x21 photo / print. (Actual opening size is 11.5x20.5) Matting Material is Crescent Mat Board. Maroon Finish / Cream Core with White Backing (PH Neutral). This listing includes (1) Custom Cut Mat. (The size selected represents the OUTSIDE dimensions of the matting.)