NSI TA45 Normally Open Push to Close Switch, 12-24VAC/DC, 2 Amps Current

I used this switch to replace one that is part of an alarm system. This is mounted on the inside jamb of an exterior door so that when the door is closed, the circuit is closed. When opening the door, the circuit opens and the alarm, if set, will sound. In case anyone was not sure, normally open means the switch is breaking a circuit when it is at rest (basically, sitting in the box). When the plunger is depressed the circuit is closed (electricity flows through it). This worked fine, but not a one for one replacement of what I had. I had to clear some wood from behind it because this switch is deeper than the old one. But, it worked out and it works as expected.

The switch fit nicely in the door jam. The wire took a bit of time to connect. Has been working for 9+ months.

Well this product was a ok replacement for the other type that I've had for 22 yearsthat is it fit right in the same hole. I wish these had wires coming off of them rather than you wrapping yours around two little screws that could come loose over time possibly. It seems to be a little bit frail. The reason I think that is the hole was just a tiny bit tight so I pushed it in and since it was kind of squeezing on the body of the switch the ball pushed in and didn't come back out. So I remedied this by pulling it out of the hole just a hair and so it was a little looser? Now it seems to be working. You can't beat the price but Ive got to wonder how many years this is going to work, I highly doubt it's going to last as long as my original but I couldn't find any other.

Excellent piece of equipment. The metal ball contact far exceeds the the comparable plastic one

I bought 3 of these and one was DOA. They're pretty cheaply constructed, but if you don't plan on installing them in a challenging location, it'll probably be OK.

Switch used as door monitor for alarm system. Installed and found the movable ball that is pushed in by the door sticks about every other door closing. Pushing by hand confirms that the ball hangs up in the housing on a regular basis. Not a reliable switch for any application.

I ordered this as a replacement switch for my security system door jam switch. Works as advertised. I would definitely buy again.

Huge upgrade from the OEM replacement switch from Resideo/Ademco. Steel ball vs plastic egg shape shouldn't bind and should last. The only issue was the outside diameter of the housing is a tiny bit larger than the OEM. You might have to fiddle with a rat tail file, re drill, or dremel it out a little bit. Maybe 2mm or 1/32". Worth it though. This is way better built than the OEM.

Arrived on time. Works well on my door alarm. Easy connections for wires.

Simple device: At rest, the circuit is Open When the ball is pushed in, the circuit is closed. I was replacing an existing sensor and when connecting the wires, I used the small holes in the back of the sensor. The resulting connections were better and less likely to break when pushing the the device back into the door frame.

Flimsy plastic but more importantly bought both Normally Open and Normally Closed switches for my front door alarm system and both operate identically and neither shows my front door is closed when pressed. Both show door is open when pressed!