Extech RH25 Heat Index Psychrometer

Extech RH25 Heat Index Psychrometer


The Extech RH25 easily monitors heat index during hot humid days.


  • User programmable heat index/WBGT alarm
  • Built-in multiparameter sensor
  • Convenient pocket size
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Why Buy From Fondriest?


The Extech RH25 Heat Index Psychrometer features a built-in multiparameter sensor that measures heat index, wet bulb global temperature, humidity, ambient temperature, temperature, dew point, and wet bulb. Heat index measures how hot it feels when humidity is combined with temperature, air movement, and radiant heat. WBGT considers the effects of temperature, humidity, and direct or radiant sunlight. The pen-sized design makes it convenient to fit in your pocket.

Notable Specifications:
  • Temperature Range: -4 to 122°F (-20 to 50°C)
  • Temperature Resolution: 0.1°F/C
  • Temperature Basic Accuracy: ±1°F/0.6°C
  • Relative Humidity Range: 0 to 99.9%RH
  • Relative Humidity Resolution: 0.1%RH
  • Relative Humidity Basic Accuracy: ±3%RH
  • Wet Bulb Range: -4 to 122°F (-20 to 50°C)
  • Wet Bulb Resolution: 0.1°F/°C
  • Dew Point Range: -108.4 to 122°F (-78 to 50°C)
  • Dew Point Resolution: 0.1°F/°C
  • Heat Index Range: -50.8 to 401°F (-46 to 205°C) 
  • Heat Index Resolution: 0.1°F/°C
  • WBGT Range: -13 to 130°F (-25 to 54.5°C) 
  • WBGT Resolution: 0.1°F/°C
  • Dimensions: 5.5x1.4x0.7" (140x35x18mm)
  • Weight: 1.8oz (50g)
What's Included:
  • (1) Psychrometer
  • (1) CR2032 battery
Image Part # Product Description Price Stock Order
Extech RH25 Heat Index Psychrometer RH25 Compact indoor/outdoor heat index psychrometer
Usually ships in 3-5 days
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