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

I purchased this to replace a cheap unit on a NexxGarage controller. The magnetic range and quality of this unit is great. It can be configured as NO or NC.

This is exactly what I needed for my garage door sensor. I had tried a simple reed switch, like one would use on a window, but it just wasnt up to the task. This item is much hardier, and the results are more predictable - meaning no more false readings. I mounted the switch at the top of my overhead door. Because of limited mounting surface on the wall and clearance requirements on the door, I was not able to line up the magnet with the switch. But even with at 50% overlap, it reads correctly. If you are setting up a door sensor that you want to work well for a long time, this is the switch you need.

Works perfect to replace a pin switch on my alarm for my fiberglass bed cover.

Has three wires black is Colin plus one for normally open and one for normally closed . Even without instructions . Hook up black plus one other and see if it signals it closed with the door closed .

It works on my garage door. Now I can tell when it is open. Good Product.

I have 4. Two can be wired different. Either n/o or n/c depends on which wires you use. They all work great.

Good performer. Magnet will reach over 2 gap and still activate switch.

Worked great for our duckins (ducks and chickens) coop alert. Wired this in to a solar light such that the light is on at night when door is opened so we can see from the house if the coop door is still open before bed. Well made product and would be good for any outdoor reed switch application.

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.

Just what I needed for my barn roll-up door. Well pleased with all phases of my purchase.