The LiftMaster 821LMB-SENSOR is a wireless add-on door sensor for the LiftMaster myQ Smart Garage Hub model 821LMB. It enables monitoring of an additional garage door through the myQ app, providing real-time open/close status and customizable alerts. Ideal as a replacement part or upgrade when you have a second door, this compact tilt sensor mounts to the top panel of the garage door and communicates with the hub to keep your door activity in view from anywhere.
Each myQ Smart Garage Hub supports up to two garage doors, and this add-on sensor is required for the second door. Installation is straightforward: mount the sensor to the door and use the myQ app to pair it to your 821LMB hub. The sensor is battery powered, operates wirelessly, and is intended for residential garage door applications. For remote closing via myQ, your garage door opener must have working safety reversing sensors per UL 325, and the hub must be connected to a 2.4 GHz Wi‑Fi network. Compatible exclusively with the LiftMaster 821LMB myQ Smart Garage Hub; consult LiftMaster’s compatibility resources if using with other myQ hub models.