LeakFrog Water Leak Alarm 2-Pack

This thing has saved me so many headaches. My basement had some water problems, but thankfully only on the unfinished part on bare concrete. However, if it was raining very heavily and the leak was undiscovered, it would have been possible for it to reach the finished, carpeted part of the basement. While we were working to fix the root of the problem, we got these LeakFrogs so we would know immediately when there was a problem and we could stop it before it got bad. Out of the box, these did not come with batteries. That was a bit disappointing because the listing said it did come with them, but Amazon credited my account the cost of a pack of batteries, so I was able to get batteries with no (real) issue. Once I got the batteries, I tried it out. Worked great, so I put it on the bare concrete where the water comes in and waited. Sure enough, that thing started beeping like crazy one night and I was able to prevent water damage. On multiple occasions this has saved time, money and lots of stress. Now, even though we've fixed the root of the water problem, we keep one in the basement and test it every so often, just because it was such a good little tool.