Extech RH490 Hygro-Thermometer
Starting at $401.49
Starting at $321.19

Not in stock. Usually ships in 3-5 business days [?]

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  • Humidity range: 0 to 100% RH
  • Absolute humidity range: 0 to 1120 GPP (0 to 160 g/kg)
  • Temperature range: -22 to 199°F (-30 to 100°C)
  • Dewpoint range: -22 to 199°F (-30 to 100°C)
  • Wet bulb range: 32 to 176 °F (0 to 80°C)
  • Basic accuracy: ±2% RH, ±1.8°F/1°C
  • Resolution: 0.1% RH, 0.1°F/°C
  • 30 second response time

What's in the Box

  • Carrying case
  • 9V battery

The Extech RH490 hygro-thermometer is a precision hygro-thermometer specifically designed for HVAC and water damage restoration contractors. The Extech RH490 hygro-thermometer features a fast 30 second response time and an accuracy of ±2%. The dual backlit display simultaneously shows humidity or water vapor in grains per pound (g/kg) along with either temperature, dew point, or wet bulb.

The Extech RH490 hygro-thermometer features a slim, handheld design with rubberized sides for better grip and for one hand operation. The Extech RH490 hygro-thermometer has data hold and min/max functions as well as auto power off with disable and low battery indicator.