Kidde HD135F Firex Wire-In Heat Detector With Battery Back Up, Sensitivity: 135 Deg, Heat Sensor, 120 Vac Operating, Audio Alarm, Dimensions: 5 In Diameter X 2 In Depth, -20 to 100 Deg F Temperature Range, Environmental Conditions: 5 - 95 PCT Relative Humidity (RH), Mounting: Wall or Ceiling, 85 DB At 10 FT Audio Alarm, Includes: 9 V Battery, 60 HZ Frequency, Ul 217, Nfpa 72, (Chapter 10 and 11 2002 Edition) The State Of California Fire Marshall, Nfpa 101 (One and Two Family Dwellings), Federal Housing Aut