For use on INWARD swinging doors only, The Door Guardian effectively childproofs your exterior doors, providing peace of mind for you and your family. This lock resists forced entry and effectively secures, reinforces, and childproofs exterior doors. Use the Door Guardian on any exterior or basement door. The Door Guardian helps prevent wandering in groups like sleepwalking children and seniors who require supervision. Recognized as “one of the best new child safety products” by the National Safe Kids Campaign in Washington, D.C., the Door Guardian works double duty as both a security device and as a childproofing lock.