First Alert SMI100, Battery-Operated Smoke Alarm, 2-Pack

Good smoke alarm, it comes with the 9 volt battery and is very easy to install.

Great value, high quality, function well - ask my toast how I know. They are loud enough to wake the dead, which is good because I am a heavy sleeper. They fit in the same frame as my old smoke detectors.

Wonderful! Easy to install and the detector easily attaches to the base. Spending a little more is well worth not having installation issues!!!

Alarms arrived promptly and in good condition, packaged well. One caveat though, I highly recommend that you switch out the provided heavy duty 9 V batteries with your own fresh alkaline batteries. Reason being, one of the three detectors that I installed immediately started beeping a low battery warning, and upon testing the provided battery, it wasn't dead but it was very weak. The other two with the provided battery tested very strongly and were good batteries. Bottom line, pull the heavy duties, use them in something besides a smoke detector, and slap in some alkalines just to be safe. Great smoke detectors though, for sure.

Works well. Had a little smoke while cooking and set off alarm.