Architecturally Appealing Low Profile Appearance SmartSet Automatically Selects Optimal Settings for Each Space Ultrasonic Diffusers give more Comprehensive Coverage Accepts Low Voltage Switch Input for Manual On Operation Depluggable Terminal Wiring for Quick and Easy Installation Walk Through Mode Increases Savings Potential Isolated Relay Allows Sensor to Interface with Building Control Systems Dimensions: 4.50 diameter x 1.02 deep 114.3mm x 25.9mm UL and cUL listed Five year