24x36 Mat for Picture Frame White with Cream Core and 20x32 Opening Size (B222MAT) MAT SIZE: This matting fits a 24x36 frame. (frame not included) OPENING SIZE: This mat fits a 20x32 photo / print. (Actual opening size is 19.5x31.5) Matting Material is Crescent Mat Board. White 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.)