Carbon Monoxide and Smoke Alarm Battery Chemistry Alkaline Battery Location Front Battery Locking Pin No Battery Size AA Communication Protocol Not Applicable Compatible With Not Applicable Detector Type Smoke/CO Detector Features Front Loading Battery Includes (3) AA Batteries Number of Tandem Detectors Not Applicable Power Source Removable Battery Sensor Type Electrochemical Ionization Visual Alert Type Red LED Volume Level 85 dB @ 10 ft Accuracy +/-20 Percent +15 ppm (CO)