SM-226L-3Q Seco-Larm Overhead Door Mount N.C. Magnetic Contact w/ 3 Wires for N.O./N.C. Applications (One Pack)

Perfect switch to be used in a basic DC electronic circuit that detects if the garage door is opened or closed. Provides a visual piece-of-mind that the door is closed,

10/10 would bang

Had one installed, but it split in half from winter weather freezing it

Well made. Fast Delivery. I mounted it over my garage door on the wall and the Magnet bracket to the door. Will last forever up there. It has a strong magnet and activates when the Garage door opens an inch. Hooked to to a low volt LED light inside the hall leading to/from garage. Lites the way! And warns if garage is ope.

I installed two of them on my garage doors in series with my thermostat to turn off the garage heater when the doors are opened. The install was a breeze (used the black and green for n.c.) and they work flawlessly. The pieces seem to be of pretty good quality, and I assume theyll last for years. These are cheaper elsewhere, but without prime shipping.

Using as a sensor with a Raspberry Pi. Working perfectly so far. Straightforward install.

Good experience. No problems.

this shipped really fast worked perfect and was a more heavy duty design than the one it replaced.

I used these switches to put indicator lights in the house so I would know if the garage doors are open or closed. I have used a wireless type of system before, but many times got error message. These wired sensors were installed on top of wall above garage door with magnetic on the door. I wired them to a green light for close and red light for open for each door, using the N/C and N/O contact to turn on the correct light. They worked great and now have a wired system to make sure garage doors are closed.

just didnt work for me... to bulky and couldnt find a way to mount it for what I was trying to do. Quality seems good, although id like them to discuss the quality of the switch since that part is hidden.