Ideal Security Inc. SK7115 Garage Door Side Lock with Spring-Loaded Bolt Release Mechanism for Operation from Outside, Galvanized Sliding bolt side lock for garage doors Spring-loaded lock and release mechanism Can be operated from the outside, with additional accessories To lock from outside: Add SKT9303 or SKL9201 handles To install exterior handle in the center of your door: Add SK7135 latch cables To unlock from outside: Add SK278 lock cylinder