This maximum protection alarm has a patented smoke entry system that allows a direct smoke path to the photoelectric sensor to detect regular and slow smoldering fires. First Alert Nuisance-Free Technology will reduce false alarms that result from cooking and shower steam. This smoke and fire alarm includes a loud 85db sound output, powerful LED indicator, end of life signal, mute and single test/silence button so you can test your alarm regularly. Installation is easy with the simple twist lock wall and ceiling mount. This smoke detector meets UL217 standards and is backed by a 10-year limited warranty. The First Alert Slim Design Battery-Operated Smoke and Fire Alarm is the perfect low-key addition for any number of home settings.