2X Magnetic Reed Switch Normally Open/Closed NC NO Door Alarm Window Security Contact, DC 5V 12V Light (White-M38)

I use this switch with warning lights on my garage door. I install a 120v to 12v transformer in my garage next to my garage door opener. Then install two 12v lights in my room connected to my garage. When my garage door is open, the lights are on. When it is closed, they are off. I can always tell if I forget to close my garage door.

i like it

I found this magnetic switch and it was more-or-less perfect for my application, but I couldn't help but notice all of the reviews of melted units. On further inspection you'll notice that many of these reviews detail misuse of the product by passing far too much current through it, for example to a lightbulb. This item uses a lightbulb as an example but explicitly says it should run to some sort of panel. This is a switch meant for powering a relay that can actually handle the current of your application. This is a switch for a signal, not for power. This will work great for something like an Arduino, but it will not for powering truck lights. Be warned that this is totally a Chinese wholesale product and you probably cannot pass through as much current as it says, but using it modestly will yield the intended result. Realistically you should not pass through 0.5A. You don't need much for a signal.

I purchased this to make my own wired open/close detector for my garage door opener. The ability to use this both as a Normally Open or Normally Closed switch is great because I wasn't sure what mode I needed to have for my plan to work. So far it has worked flawlessly for me.

Magnetic switch worked as it should. I would recommend to others.

Both switches in the double pack failed within 30 days of installation. One failed in the OPEN position, and one failed in the CLOSED position.

The media could not be loaded.  I used this to replace other switches I bought from Amazon that only last about 2 years, which failed. They are mounted inside a custom tea cabinet I built for my wife, & off the top the Wiring diagram was backwards. They seem much cheaper than the other ones previously installed, but they are working. Not sure how long they will hold up for?But I’ll agree with other reviews, I wouldn’t use this switch for anything major or serious like controlling the garage door, or any type of security alert because it/they might fail. They make commercial switches for that sort of stuff that can be found on here, they go for about $60-$80.. If this fails on the cabinet, an led light might stay on till someone notices, no big consequences. Good luck-

So inexpensive and such a difference. Installs in fifteen minutes and transforms your closet experience. Turns light on when you open and off when closed. Very flexible installation and ease of use! Love them!

Tried all 3 switches and every combination with the magnets and nothing worked. Like others have said, NO and NC are reversed from the description which is easy to get around. Problem is all 3 of mine are either always open or always closed, not exactly what I'm looking for in a switch! Sending it back.

A great little set of magnetic switches for a decent price. I purchased these to use in a cabinet to turn an LED strip on when the door opens and they've been working great! They feel like they are built pretty well and after using them for almost a year now I have never had an issue with them.

Would have been nice if NO and NC were clearly marked.

These magnetic reed switches work better than I expected; they don't have to touch the magnet to work, as long as they get within 10 mm or so.But, the contacts are mislabelled; the NO (normally open) is actually NC (normally closed), and vice versa. I used my continuity meter on them and so relabelled them before installation, and was glad I did.I used them as sensors for an appliance garage in our new kitchen; while having a power outlet in an appliance garage is now illegal in the US, it is still legal in Canada, IF the power to the outlet is automatically switched off when the garage door is not fully open. The magnet was mounted on the moving door, the switch on the wall where the door stopped when fully open, and the contacts switched a safe 24VDC circuit (power adaptor also from Amazon) to control a 20A power relay from Grainger (Functional Devices). The end result works extremely well, and made my wife very happy.The electrician who installed the system was also impressed.

product works Ai .being used for door alarm