These work as perfect replacements to both my window and door sensors on my alarm system. I was able to pop out any non-functional sensors, screw the 2 wires into these sensors, and push these sensors back into the same hole with zero issues.

I like the size of these sensors, but beware as they are for 3/4" gap and the reed switch can become magnetized and fail to open (sense the door/ window open). I would prefer higher reliability, or prefer that they fail to close rather than open.

I haven't used these yet, but the holes and screws for the wire connections are very small. I hope I can use them.

These work perfectly for replacing worn out sensors on my home security system. The magnets are strong & reliable, and the sensor switches are so easy to install - just insert 2 wires & tighten set screws with a screw driver. Really easy to use with minimal 'handiness' or DIY skills required if you need to repair/replace your hard wired home security system sensors. I'm very glad I was able to find these and do my own repairs. My security company wants to replace damaged sensors with gaudy wireless sensors that fall off and require batteries. The wireless ones are such and eye-sore! I much prefer my hardwired, hidden sensors. These are great!

Great!! Replaced my 15 year old sensors. Easy install and works great.