If you already own or plan to purchase a Channel Vision Cat. 5 Whole House Intercom System, this relay module it the perfect accessory. It will increase home security and convenience by adding entry/access control to your property. The Channel Vision CAT. 5 Intercom Relay Module provides contact closure that will activate an electronic door strike or a gate opener, each sold separately. When a visitor arrives, they will buzz in using a door station intercom and using any CAT. 5 Intercom Station you can verify who your guest is and open the door or gate. This versatile module has a durable stainless steel cover and fits into a single-gang box for easy installation. The addition of this relay module to your CAT. 5 Whole House Intercom System will help prevent unwanted visitors from accessing your property and offers an easy solution to remotely allow guests to enter your home.Other Features # Relay setting for Normally Open (N.O.) and Normally Closed (N.C.) operation # Variable relay times: 8 seconds, 20 seconds, 90 seconds, 200 seconds # LED indicators for easy trouble shooting