original antique american made exterior residential doorknob oversized backplate likely fabricated by russwin, sargent or possibly lockwood. the doorknob escutcheon is comprised of stamped wrought ornamental brass metal with a largely uniform surface finish. contains two screw holes and a protruding collar or thimble. large circular opening for a cylindrical lock. measures approximately 10 7/8 x 2 7/8 inches.