HT605 Digital Portable High-Precision Air Volume Tester Wind Speed Meter Handheld Measuring Wind Speed Tools This is A professional digital with stable performance, safety and reliability. It is widely used in wind energy, meteorology, industry, agriculture, hydrology and water conservancy, environmental protection, highways, airports and ports, etc. Data hold;Backlight on or off;MAX/MIN/ function;Temperature unit ;Wind speed unit ;Auto shutdown function. Size: 137x56x26mm Display: LCD display, maximum display 9999 Wind speed measurement: Range: 0.70 - 30.00 m/s Sampling time: about 0.5 seconds / time Sensor: impeller + Data Hold: Lock display readings Operating environment: 0-40C, maximum relative humidity of 80%, altitude Less than 2000m Storage environment: -10-50C, max 70% relative humidity (battery removed) Automatic shutdown: 10 minutes Power supply: 3 x 1.5VAAA(LR03) batteries (battery not included) Wind speed accuracy: Less than 1.00m/s: 0.7 m/s; 1.00~30.00 m/s: (2.0%+ 0.5m/s) Temperature range: -20.0C - 60.0C (-4.0F~140.0F) Temperature Accuracy: 0.0 C ~ 45.0C: 1.0C; Others: 1.5C Humidity range: 0.0% ~99.9%RH Humidity accuracy: 20%~ 80% RH: 5.0%RH; others: 6.0%RH Considerations: 1.Do not touch the fan blade with force. 2.Do not or operate the instrument in areas with high temperature or humidity. 3.In use, do not let the strong light directly shine on the fan, in order to avoid measurement errors. 4.Avoid violent vibration. 5.Remove the battery storing the instrument for a long time. Colour:black+red Material:ABS Package Contents: 1 X 1 X Instructions Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the a little different from the real thing. The measurement allowed error is +/- 1-3cm.