Smoke Alarm, Battery Chemistry Alkaline, Battery Location Front, Battery Locking Pin Yes, Battery Size 9V, Communication Protocol Wireless, Compatible With Not Applicable, Detector Type Smoke Detector, Features Front Loading Battery, Includes Alarm Latch Indicator, Mount Bracket, Number of Tandem Detectors 24, Power Source Removable 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