Need to monitor more than one station with your Voice Alert System? Adding these additional sensors is no problem; the system is capable of handling up to 6 sensors per base unit therefore giving you the ability to monitor up to 6 different zones. Each sensor is designed to monitor an additional zone. System-6 monitors up to six zones using wireless PIR Sensors/Transmitters and a remote Receiver/Speaker Base Unit.Each sensor has a monitoring range of approximately 40' x 40' and is fully adjustable when mounting (rotating and pivoting). The sensor's method of detection is pyroelectric infrared detection (heat) and is weatherproof. The Voice Alert System-6 combines wireless and digital voice technology to create the most flexible and cost-effective annunciation system available today. When a zone is breached, a signal is sent up to 1000 feet (300' through walls) to the remote base unit. The system includes one sensor and a base unit, which plays a user (voice-recorded) message identifying that specific zone when the sensor is triggered.