GS-MT Skylink Wireless Garage Door Sensor for SkylinkNet Connected Home Alarm Security & Home Automation System and M-Series. Track and Monitor your Garage Door open or closed status Remotely monitor the status of your Garage Door Monitors Garage Door open/close; Tilt sensor; Wireless range up to 600 feet in open area (Sensor to HU-100 Internet Hub or M-1 Main Console/Indoor Siren) Compatible with SkylinkNet iOS Apple & Android App and M-Series Lifetime Support: Toll Free 1-800-304-1187; Email: support@skylinkhome.com