FIRST ALERT SCO500NVA CO and Smoke Combination Alarm

AA battery-operated/wireless interconnect. Optipath 360 technology - patented photoelectric smoke sensing design. Advanced electrochemical CO sensor. Spread spectrum horn - easier for elderly with normal hearing loss to hear. Two Latching features - alarm latch and low battery latch. Two silence features - silence low battery chirp for up to 8 hours or, temporary silence nuisance alarm conditions. Add additional battery-operated First Alert ONELINK enabled alarms to create a wireless safety network. 7 year warranty.