[3In1 Multi-functional Heat Stress Meter]This -881W anemometer has Real-time/MAX/MIN/wind speed reading function, and can also measure wind temperature/ humidity/ black ball temperature. The -881W is your for measuring the weather and surrounding climate. [High Precision Wind Speed Meter]The -881W wind velocity velometer is equipped with 7 sensitive wind vanes for more accurate measurement. Wind speed range: 0~30m/s, resolution: 0.1m/s ( Accuracy:5% Digit ). Multi-unit switching allows you to select different wind speed units (m/s, km/h, ft/min, knots, ) [Temperature & Humidity Meter]With the function of measuring ambient temperature and humidity, temperature range: 0~50(Accuracy:0.6), switchable temperature unit /; humidity range: 0.1%~99.9%RH (Resolution: 0.1%RH). [WBGT Alarm]This -881W heat stress meter has WBGT alarm function, WBGT temp.range: 0~50, WBGT Alarm Range:20~50. The WBGT alarm function can be used to monitor the surrounding climate and reduce the harm to the human body caused by the dangerous environment of humidity and high temperature. And the 4-level screen displays heatstroke danger zone indications to help you easily understand the danger zone. [Wide Range of Applications] The -881W heat index stress meter air globe temperature humidity tester is an essential measurement tool for HVAC systems, drones, , surfing, sailing, kite flying, climbing, home appliance maintenance, other outdoor activities and industrial production. Heat index can also be used for buildings, steel foundries, brick factories, glass facilities, boiler rooms, mining areas, training, marathons, seaside activities, etc. [More Extra functions]With a large screen LCD display and backlight function, you can use this air flow gauge weather meter to work in a dark environment and easily read data. Low battery indicator---when the battery symbol appears on the LCD screen, it means the battery is low. and portable--- it is very convenient to carry whether for work or travel. Wind Speed Range: 0~30m/s Accuracy of Wind Speed: 5% Digit Resolution: 0.1m/s Wind Speed Unit Selection: m/s,Ft/min,Knots,km/h, Temperature range: 0~50 Accuracy of temperature range:0.6 Resolution:0.1 Humidity range: 0.1%~99.9%RH Humidity resolution: 0.1%RH WBGT temp range: 0~50 WBGT Alarm Range: 20~50 1.5V(AAA) x 2 batteries not included Colour:yellow Material:ABS Package Contents: 1 x -881W Digital Anemometer 1 x English manual 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 picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.