HP-866A Digital Portable Anemometer Wind Speed Gauge Air Temperature Meter Thermometer with USB Port Condition: Item Type: Anemometer Material: ABS Function Unit Wind Speed  Resolution    Accuracy      Wind Speed Rangem/s0.80-40.000.01±2%Ft/s1.30-131.200.01±2%Knots0.80-77.700.01±2% kilometer /h1.40-144.000.01±2% miles per hour 0.90-90.000.01±2%Ft/m78.00-78741±2%Air Volume Range UnitRangeArea CMS(M³/Sec.）0-99990-9.999㎡CMM(M³/MIN）0-999900-9.999㎡ CFM(FT³/MIN）0-999900-9.999ft²Unit  Conversation m/sFt/minKnots kilometer /hMiles per hour m/s1196.871.9443.62.24Ft/m0.0050810.009870.018290.01138Knots0.5144101.2711.85191.1523 kilometer /h0.277854.690.5410.6222 miles per hour 0.446487.890.86971.60711Air Temperature Range UnitScaleResolutionAccuracy°C -10.0-60.00.1±1.5°C°F14.0-140.00.1±2.7°FRelative Humidity RangeResolutionHumidity（20~80）%RH0.1%RH3%RH@25°C(<20 or >80)%RH0.1%RHConnect to PC with USB Battery1.5V  AAA x 2 (not included)