A non-reversible mortise lock made by R & E that is a LEFT hand only lockset. The lock measures 3-7/8" x 5-5/8" x 3/4'' thick case with the edge plate being 1-1/4" x 7-3/4 inches long. The cast bronze door plate measures 3" x 16 inches long and are in the "Jerome" pattern by Russell & Erwin. This lock doesn't have a deadbolt, but instead has the push buttons on the face plate to lock the outside door knob from turning. The knobs are a little unusual because they are in 3 parts, to remove you must loosen the shank collar behind the knob to remove from the spindle.