The Miller Edge MIRM-T2 Patriot 2 non-contact infrared sensing edge system for motorized sectional overhead commercial doors is a DIY safety system that will signal your door's motor to stop and reverse when an obstacle is sensed. This non-contact sensor system with hardware from North Shore Commercial Door includes a light-emitting infrared eye and receiving eye that will mount to and travel with your door's leading edge. When an obstruction blocks the infrared beam, the door operator's motor is signaled to stop and reverse the door's movement. In addition to obstacles, the water-resistant photo eye system will signal the motor to stop and reverse when a loss of power or short is detected. Your kit includes two telescopic arms, two mounting brackets, one receiving eye, one emitting eye, a coil cord and junction box.