... battery warning, non-false alarm. Widely used for rolling door, shutter door, garage door.Specification: 1. Triggered distance :< 6 cm2. Working ... you are on the 8th floor, but your garage is on the first floor. You can install ... in your home, and extend the wire into the garage.5. Open the cover of transmitter, fix battery ... it on the wall, even pin it up by screw.9. if Green low battery LED turns on, ...