The RY-24L Door Release Relay Module is an interface between the door strike contacts on the Aiphone monitor and the actual release mechanism. The contact closure directly out of the monitor is rated at 12V AC with a low current capacity. If your strike or maglock requires more voltage or current, the RY-24L is required. It provides either a Normally Open contact for an electric strike, or a Normally Closed contact for a magnetic lock. The contact rating supports a majority of door release hardware available on the market. The RY-24L relay is recommended with all KC, KB, and JA video systems when using the door release feature.