Compatibility: The 41A4373A sensor works with for liftMaster and for chamberlain openers from 1993 to the late '90s and supports various for liftMaster residential and commercial ATS models. (provided they are already equipped with sensors) Upgrade: Made of high-quality ABS, the 41A4373A door sensor is rigorously tested for durability and reliability. It features a yellow safety label for visibility in industrial settings and has a 30-ft operating range. Installation: The 41A4373A(infrared eye)safety sensor features a center hole for bolt mounting to a bracket, allowing quick setup. Note: Turn off the opener's power before installation! Includes:Each sensor has a green light and center bolt for alignment. The set includes a sender, receiver, wire connectors, no brackets included. NOTE!: This is a compatible replacement, not-original. Brand names are for reference only. We aim to provide high-quality products. Color:Black Material:plastic Package Contents: 2 * sensor 1 set * accessories Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.