Human Presence Sensor adopts microwave radar technology and utilizes doppler principle. So it can sensitively detect human motion and output the presence signal of human body.The LifeSmart Human Presence Sensor adopts microwave radar technology and utilizes the doppler principle. So it can sensitively detect a humans motion and output the presence signal of the human body. It features a super mini sized sensor that offers very high sensitivity regardless of its compact size. A super wide detection range makes the product more efficient and its resistance to environmental interference makes it more reliable. FEATURES: Super