Ensure the safety of your loved ones with the First Alert(R) smoke alarm operated by a 9 V replaceable battery. The low-profile detector comes equipped with an ultra-reliable photoelectric sensor to provide rapid detection of regular and slow-smouldering fires. The unit features nuisance-free technology which reduces false alarms that result from cooking and shower steam and includes a loud 85 dB sound output. The smoke alarm is also equipped with and a powerful LED indicator, end of life signal, and a mute and single/test silence button. This product is backed by a 10-year limited warranty.