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Micro Store -> Inspection Tools & Equipment -> Psychrometers -> Extech RH300 Hygro-Thermometer Psychrometer

Extech RH300 Hygro-Thermometer Psychrometer

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External Probe Temperature measurements for differential.


  • Simultaneous display of %RH, Temperature and Dew point or Wet Bulb or Probe Temperature
  • Wet bulb measurements without slinging
  • Calculates T1-T2 differential (Air Temperature minus External Probe Temperature) using optional probe TP890) and T-2 Dew Point
  • Unique sensor cap design twists to closed position for protection during storage
  • Switchable °F/°C temperature units with 0.1° resolution
  • Data Hold freezes current reading on display
  • Max/Min readings
  • Auto power off to save battery life
  • RH300 complete with 2 AAA batteries
  • Optional external temperature probe (TP890)
  • Optional kit: RH305 includes RH300, temperature probe, 33% and 75% calibration bottles, and carrying case

Available Options/Accessories

RH300 Hygro Thermometer Psychrometer $99.99 Add To Cart
RH300 NIST Certified $220.99 Add To Cart
RH300-Cal Humidity Calibration Kit $59.99 Add To Cart
RH305 Hygro-Thermometer Psychrometer $149.99 Add To Cart
RH305-NIST Hygro-Thermometer Psychrometer - NIST Certified $274.99 Add To Cart

Download Catalog

Looking for more products from Extech? We carry many more products than we are able to list on our website. Click here to download the full Extech catalog. Then contact us to place your order!

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RH305 Kit