Extech RH490 Precision Hygro-Thermometer

Extech RH490 Precision Hygro-Thermometer


The Extech Precision Psychrometer simultaneously displays humidity or GPP (g/kg) plus temperature, humidity or GPP (g/kg) plus dew point, or humidity or GPP (g/kg) plus wet bulb.


  • Less than 30 second RH response time
  • Water vapor in GPP (g/kg)
  • Slim design with rubberized sides allows for a better grip with one-hand operation
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Why Buy From Fondriest?


The Extech Precision Hygro-Thermometer has a high 2% relative humidity accuracy with grains per pound and grams per kilogram. The meter has a less than 30 second response time and its slim design with rubberized sides make for a better grip for one handed operation. The dual backlit screen simultaneously displays humidity or GPP (g/kg) plus temperature, humidity or GPP (g/kg) plus dew point, or humidity or GPP (g/kg) plus wet bulb. Additional meter features include data hold, min/max function, automatic power off with disable, and low battery indicator.

Notable Specifications:
  • Humidity range: 0 to 100%RH
  • Temperature (internal) range: -22 to 199°F (-30 to 100°C)
  • Basic accuracy: ±2%RH, ±1.8°F/1°C
  • Maximum resolution: 0.1%RH, 0.1°F/°C
  • Dew point range: -22 to 199°F (-30 to 100°C)
  • Wet bulb range: 32 to 176 °F (0 to 80°C)
  • Absolute range humidity: 0 to 1120GPP (0 to 160g/kg)
  • Dimensions: 7.8x1.7x1.3" (200x45x33mm)
  • Weight: 7oz (200g)
What's Included:
  • (1) Meter
  • (1) Carrying case
  • (1) 9 V battery
Image Part # Product Description Price Stock Order
Extech RH490 Precision Hygro-Thermometer RH490 Precision hygro-thermometer
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Extech RH490 Precision Hygro-Thermometer RH490-NIST Precision hygro-thermometer, NIST traceable
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