Extech 45158 Mini Thermo-Anemometer with Humidity
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  • Display Air Velocity and either Relative Humidity, Dew Point, Temperature or Windchill
  • Selectable averaging function of 5, 10, or 13 second intervals
  • Fold up protective housing extends to 9" (229mm) for better reach, Tripod mount
  • Data Hold with Auto power off
  • Water resistant housing floats

The Extech 45158 mini thermo-anemometer with humidity features a waterproof, pocket size design. Capable of measuring a number of factors, the Extech 45158 mini thermo-anemometer is a handy item for a number of applications. The Extech 45158 mini thermo-anemometer measures air velocity from 100 to 5500 ft/min (or equivalent) with an accuracy of ±3% of reading; temperatures from 0 to 122°F (-18 to 50°C) with an accuracy 1.8°F (1°C); relative humidity from 10 to 95% with an accuracy of ±4%; and dewpoint from 32° to 122°F with an accuracy of ±2%.

All data is displayed on the Extech 45158 mini thermo-anemometer's 9999 count LCD screen, which can display air velocity and either relative humidity, dew point, temperature or wind chill. Other features of the Extech 45158 mini thermo-anemometer include selectable averaging function of 5, 10 or 13 second intervals, tripod mount, data hold, auto power off, and water resistant housing that will float.

The Extech 45158 mini thermo-anemometer comes complete with CR2032 lithium battery and 43" (1.09m) lanyard.


Temperature Range0 to 122 °F
Temperature Resolution0.1°F
Velocity Range0.5 to 28m/s
Temperature Accuracy±1.8°F
Operating Temp0 to 122 °F
Power SupplyLithium Battery
Battery Life100 hr
Velocity Resolution0.1m/s
Velocity Accuracy± (3%rdg + 0.2m/s)
Additional InformationMeasures RH from 10% to 95%
Pressure RangeN/A
Pressure AccuracyN/A
Time ConstantN/A
Relative Humidity Range10% to 95% RH
Relative Humidity Accuracy± 4% RH
Relative Humidity Resolution1%
Volumetric Flow RangeN/A
Volumetric Flow AccuracyN/A
Volumetric Flow ResolutionN/A
Please consider these optional accessories.
Extech Spare Mini Impeller Assembly
Mini impeller assembly for the Extech 45118 and 45158 airflow meters
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