This horizontal style lock box mounts to the surface of a door near its edge. The keeper is then mounted to the frame next to the lock box. This rim lock could go on either a left-hand door or a right-hand door. The plunger can be turned over for either purpose. The push button that locks the plunger is on the side of the box (not on the top or end as so many others). This is a heavy cast iron box that has only some of its original factory paint. You might want to repaint this one.
The rim lock measures 4 1/4 inches long and 3 1/4 inches tall (vertical), and 3/4 inch thick. The spindle hole is 3/4 inch in from both edges. The keyhole is 5/8 inch from the bottom of the box and 1 3/4 inches from the edge. A key will be included.