With a simple push of a button it is easy to reach someone in a noisy area or someone who has difficulty hearing. This battery-operated system consists of a small, vibrating/chime receiver and a push-button transmitter. It works up to a range of about 100 feet both indoors and out and through most barriers. Vibrating receiver is approximately the size of a cigarette pack and includes a clip that attaches to the user's belt or clothing. Uses 2 AA batteries (not included). One year warranty. This product can help supplement other methods of caring for people but is not recommended for exclusive monitoring.