Carbon Monoxide and Smoke Alarm, Battery Chemistry Alkaline, Battery Location Back, Battery Locking Pin Yes, Battery Size AA, Communication Protocol Not Applicable, Compatible With Not Applicable, Detector Type Smoke/CO Detector, Features Voice Alert, Includes AA Battery, Number of Tandem Detectors Not Applicable, Power Source Removable Battery, Sensor Type Photoelectric, Visual Alert Type LED, Volume Level 85 dB @ 10 ft, Battery Backup No, Form Factor Slim Profile, Hush Mode Yes