Accurately install Schlage CO cylindrical series locks using the HIT-146N Drill Guide. This unit, thru-bolts to door, using the existing 2-1/8” crossbore for alignment. All required mounting and function holes including the DPS switch in the door edge are located with hardened drill bushings. There are drill bushings on both sides of template, to allow drilling from either side of door. This drill guide will template both wood or steel doors. Standard drill guide will accommodate doors up to 2” thick with a 2-3/4” Backset. DPS drill guide will center on a standard 1-3/4” door.