SEHOMY 1 Pack WiFi Door Sensor Alarm, Smart Door Open Contact Sensor Realtime APP Notification Compatible with Alexa Google Assistant, Home Security for Safety, Wireless Window Detector Burglar Alert

I put this on my storage container behind my garage that I like to forget to lock!

We use this as a door alarm for our store. We can be in other parts of the store or even down the block and an alarm sounds on our phone when someone enters.

Uses batteries like crazy, only lasts about 2 or 3 weeks, could be bad batteries but holy crap. It works though when the batteries are working, and links with Alexa pretty easy too

This device technically does everything it claims, but I found Wi-Fi coverage to be short and actually detecting an opening was not reliable and very delayed most of the time. As a result, I don't know that it actually solves a problem for anyone practically speaking.

You can't beat this sensor for the price! Prior to installation, I had to split my wireless gateway to reflect 2.4ghz and switch from the 5ghz on my phone over to that one. Once installed, I was able to reconnect my phone to the 5ghz connection and the door sensor still works just fine. Overall very easy installation and I'm notified within seconds on my phone and Samsung smart watch if my front door opens. The only thing that will probably be annoying is the sticky tape when it's time to replace the batteries because I'll have to pull it from the wall with no guarantee it'll restick. Thin Velcro would probably be a smarter option for when I have to take it down and reattach it. Very happy with my purchase