Custom 15x21" Matted Picture Frame with 11x17" Single Mat Image Opening Framed in 1.25" Satin Black and choice of 2" 4-ply, pH Neutral White Core Mat. Comes with Economy Acrylic and a a wire hanging set for wall mounting! Made of MDF - this one of a kind custom picture frame will enhance any piece of art you put in it! . This frame comes with one pH Neutral Mat with a White colored core. Fits 11x17" art or photos. Actual frame size (finished size) is 17x23". Actual glass size (inside size) is 15x21". This frame is 1.25" wide and 0.7500" high. It has a 0.25" lip (the part that covers the mat) and a 0.4375" rabbet (space between the lip and back of the frame).