Similar in functionality to Parallax's PIR sensor (555-28027), the wide-angle PIR sensor features a larger detection angle of 180°. This makes it ideal in applications where users need to track movements across a large, open area. The wide-angle PIR sensor is a pyroelectric device and it detects motion by sensing changes in the infrared levels emitted by surrounding objects. When motion is detected, the wide-angle PIR sensor outputs a high signal on its output pin.