This sliding door multi-point mortise lock is constructed of diecast metal and aluminum components, and it comes with a chrome plated, rounded faceplate. Typically used on sliding patio doors, it features a two-point latching mechanism whose hooks face away from each other at 3-3/4 inch on center. The mounting holes are spaced apart at the distance of 7-13/16 inch on center, and the housing measures 9/16 inch thick. When the hooks are engaged and locked it secures you door better than a single hook lock in just one direction. As a newer product, the style mortise lock has a button in the center of lock. The button needs to be depressed to operate lock. This feature is to prevent you from closing door and breaking each latch hook. When door is closed the button will depress and allow you to lock door. The correct keeper will allow this.