Review on ARDWOLF Photoelectric Smoke Alarm – 2 Pack Fire Alarms | UL Listed, Battery-Operated with Included 9V Battery | 10-Year Life span | Essential for Home Fire Safety by Mike Wachtel

My old First Alert smoke alarms finally stopped working after about 10 years. What frustrated me the most was how difficult it was to put new batteries in. I was afraid of it. These smoke alarms are much better when it comes to battery installation.***** The alarm cannot be wall mounted without a battery installed. Inside, under the battery, is a small clip that needs to be pushed by the battery to allow the back to fit in the metal detector. After about a year, listen for a faint beep that alerts you to replace the battery.