Smoke Alarm Battery Chemistry Alkaline Battery Location Back Battery Locking Pin Yes Battery Size 9V Communication Protocol Wireless Compatible With Not Applicable Detector Type Smoke Detector Features Safety Light Alarm Memory Includes Not Applicable Number of Tandem Detectors 24 Power Source Sealed Battery Sensor Type Ionization Visual Alert Type Green LED Red LED Volume Level 85 dB @ 10 ft Alert Type Sound Battery Backup No Detects Smoke