Heat Alarm Battery Chemistry Alkaline Battery Location Back Battery Locking Pin Yes Battery Size 9V Communication Protocol Wireless Compatible With Not Applicable Detector Type Heat Detector Features Interconnectable to Smoke Alarms for Protection of Garages and Attics Includes Tamper Resistant Pin Number of Tandem Detectors 18 Power Source Removable Battery Sensor Type Thermistor Visual Alert Type Red LED Volume Level 85 dB @ 10 ft Alarm Setting 135 Degrees F Alert Type Sound