Part of the best bedwetting alarm system out there! We tried several, and my son complained that many were not comfortable, or the alarm was not loud enough to wake him. This one works! This is an extra/replacement receiver for the Rodger Wireless Bedwetting Alarm System. Nice to have an extra to leave at grandma’s, etc. The receiver is the part that makes the alarm sound. You can plug it into the wall or use batteries. It will pair with your Rodger transmitter (can order whole system at The Bedwetting Store website). Directions to pair are on The Bedwetting Store website as well. Works perfectly!