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 Red Pulses During Alarm and Green Once Every 30 Seconds Increased Sensor Life 7 Years Includes Battery Number of Tandem Detectors Not Applicable Power Source Removable Battery Sensor Type Electrochemical Visual Alert Type LED Volume Level 85 dB @ 10 ft