This extremely well made, heavy duty mortise lock, was widely used by builders and carried by Russwin in the late 1920's and well into the 1930's. This model was a feature model in Russwin's 1930 catalog. Russwin (Russell & Erwin) was one of the foremost manufacturers of American builders hardware in the late 19th and early 20th Century. The Brass front plate measures 5 1/4" by 15/16" wide by 1/8" thick. The box is 3 3/8" deep from the back of the front plate and it is 3 5/8" top to bottom. Screws are on 4 1/2" centers. The backset (the distance from the front edge of the brass faceplate to the center of the knob post hole) is 2 1/2". The lock is reversible, extremely well made, and lightly restored ( a new stainless steel lock spring has been installed, the internals have been cleaned and oiled, the knobs and knob plates have their original hand rubbed patina). Unfortunately the key is missing. Please see photos for further details as the item pictured is the exact item you will receive. See my other listings for more great items.