Digital Psychrometer + InfraRed Thermometer
extech RH401


  • Triple display with backlighting
  • View Air temp+RH+surface temp
  • View Dew Point+RH+surface temp
  • View Wet Bulb+RH+surface temp
  • InfraRed Thermometer with Built-in laser pointer
  • 8:1 distance to target ratio
  • Adjustable Emissivity from 0.3 to 1.0
  • Precision humidity capacitance sensor is retractable for protection during transportation and storage.
  • Calculates T1 (IR Surface Temperature) - DP (Dew Point) differential

   Precision Hygro-Thermometer
extech RH490

Highest 2% RH accuracy with Grains Per Pound (GPP) Display

  • Less then 30 seconds of RH response time
  • Water vapor in GPP
  • Dual backlit display
  • Simultaneous display of:
    • Humidity/Temperature
    • Humidity/Dew Point
    • Humidity/Wet Bulb
  • Slim design with rubberized side grips
  • Data Hold and Min/Max functions