Carbon Monoxide and Smoke Alarm Battery Chemistry Lithium Battery Location Not Applicable Battery Locking Pin Yes Battery Size 3V Communication Protocol Not Applicable Compatible With Not Applicable Detector Type Smoke/CO Detector Features 2 In 1 Protection 10 Year Sealed Lithium Battery Low Profile Round Design Alarm Status LED Indicator End of Life Signal Test/Silence Button Includes Mounting Anchors Screws Number of Tandem Detectors Not Applicable Power Source Sealed Battery