Carbon Monoxide Alarm Battery Chemistry Alkaline Battery Location Back Battery Locking Pin No Battery Size 3V Communication Protocol Not Applicable Compatible With Not Applicable Detector Type CO Detector Features Sealed Lithium Batteries Red LED Pulses During Alarm Digital Display of CO Levels Includes Not Applicable Number of Tandem Detectors Not Applicable Power Source Sealed Battery Sensor Type Electrochemical Visual Alert Type Green LED Red LED Volume Level 85 dB @ 10 ft