A key-in-knob lock by itself makes entry into a residence a simple matter. All entry doors (and possibly some interior doors) should be equipped with some form of deadbolt lock. When purchasing a lock, there are three primary things to look for: 1) a deadbolt with at least a 1" projection —— the bolt should extend at least 1" from the front edge of the door; 2) a heavy tapered steel guard ring protecting an outside key cylinder that spins freely around the cylinder —— this protects the outside key cylinder from being twisted off with a pair of pliers or other tools; 3) at least two.
