Kidde Combination Smoke Carbon Monoxide Alarm Battery Operated Wireless-Interconnected

The alarm is powered by 3 AA batteries and features a voice alarm that warns of smoke or carbon monoxide danger. The voice alert also lets you know when it's time to replace your batteries. This alarm features wire-free interconnectivity with other Kidde KN-COSM-B-RF units (up to 12 total). If one unit is triggered, all interconnected alarms will sound. Wire-free interconnectivity allows for easy interconnect setup and eliminates the need for expensive rewiring. You can even install this smoke detector in a detached garage or workshop and be alerted by another detector in the house.