The Traphouse measures 13 inches wide and is 6 inches tall. In your indoor shooting environment (where you are standing 8 to 12 feet from the wall) it appears the same size as a real traphouse does at 16 yards. Therefore, when you mount your gun in relation to the DryFire 3D Traphouse the visual distances you see at the muzzle of your gun accurately simulate what you see at your local gun club.