Logo for Judge Tool and Gage
EXTECH - Precision Hygro-Thermometer - RH490

EXTECH - Precision Hygro-Thermometer - RH490

Starting at $388.99
Highest 2% RH accuracy with Grains Per Pound (GPP) Display
  • Anyone whose job relies on calculating humidity levels will appreciate the Extech Hygro-Psychrometer. 
  • In addition to measuring relative humidity in 30 seconds, this handheld instrument captures dew point, wet bulb, temperature and water vapor levels (Grams per Kilogram and Grains per Pound).
  • This utility tool will store maximum and minimum readings until the memory is cleared and includes a data-hold button for rapidly fluctuating measurements.
  • Complete with carrying case and 9V battery.
Additional Information +
Item No. Our Price QTY
RH490 $388.99


Data Sheet Manual


  • Quick response
    • Less than 30 seconds of RH response time.
  • Easy to use
    • Simultaneous display of: Humidity/Temperature, Humidity/Dew Point or Humidity/Wet Bulb.
  • Data hold and min/max functions
    • Includes a data-hold button for rapidly fluctuating measurements.