early 20th century antique american exterior residential entrance door "chatham" pattern doorknob backplate fabricated by the russell & erwin mfg. co., new britain, ct. the oversized escutcheon contains a large opening for a cylinder lock. the wrought brass collar or thimble is tightly fastened to the backplate. nicely aged surface patina left intact. unique twist motif border with detailed acanthus leaves surrounding the screw holes. measures approximately 12 x 3 1/4 inches.