Carbon Monoxide Alarm Battery Chemistry Alkaline Battery Location Back Battery Locking Pin No Battery Size AA Communication Protocol Not Applicable Compatible With Not Applicable Detector Type CO Detector Features Sealed Lithium Batteries Red LED Pulses During Alarm Event Memory Includes Battery Number of Tandem Detectors Not Applicable Power Source Removable Battery Sensor Type Electrochemical Visual Alert Type Green LED Red LED Volume Level 85 dB @ 10 ft Alarm Setting 30 ppm