Finally, one smoke alarm that can be hardwired, battery-powered, interconnected, or stand-alone – no need to purchase separate alarms for different installs. The built-in 10-year battery can be the primary power source or the backup power source when installed using the 240V hardwired option. Use Emerald’s Hybrid Smoke Alarm as a stand-alone alarm or interconnected – either wirelessly with the addition of the RF module (sold separately) or hardwired connection.