Window Alarm 4 Packs - Loud 120dB and Vibration Sensors Compatible With Virtually Any Window - Glass Break Security Sensor - Low Battery LED Indicator

They do work especially if I open the patio door and forget to turn it off! The flashing light is hopefully a deterrent and the sticker on the back that goes against st the wi down another warning. Highly recommended

These are very loud, on par with a smoke detector. They were easy to install and they are sensitive. My dog likes to look out the window and when she hit the window it went off. Definitely worth the price.

One of the teeth is broken

Works great

These window alarms are excellent. We have an older home with a few basement windows. I installed one alarm on every window. Pros: good size, warning sticker and light alert that the windows are alarmed (and the light means you know if the batteries have power), can be placed anywhere, on-off switch, easy battery access, extreeeeeeemely loud (my cat set one off - it could be heard outside, throughout the house, and was so loud that I could barely think even with ears covered to go switch it off and back on), sensitive. Cons: unknown as to whether they can be removed and reused due to the sticker attachment. It would be nice if 3 were included per alarm. Highly recommend as an extremely easy, affordable, and quick security update. Anyone can install them.

Muy bueno la alarma se escucha bastante fuerte, solo aveces he probado y no se activa, no se si necesite mas sensibilidad