The HC-SR501 is a PIR motion detector with an adjustable range that can sense up to 7m. The sensor uses infrared technology and features high sensitivity, ultra-low voltage mode, high reliability, and is ideal for using in battery-operated equipment. This sensor is designed for use in security products, alarm systems, lighting control, industrial automation, toys, etc. * 7m Sensing range * Wide voltage range * Low power consumption * Adjustable delay * Temperature compensation