original early 20th century antique american residential entrance door backplate, likely fabricated by russwin or lockwood. the oversized doorknob backplate is made of stamped brass with intricate leafage surrounding a centrally located cartouche. the wrought brass thimble or collar remains tightly affixed to the backplate. the cylindrical hole provides for installation of a cylinder lock. mostly uniform surface patina. measures approximately 10 x 2 3/4 inches.