The Anemometer is a mini wind speed and wind temperature tester. This light weight device is equipped with the latest magnetic sensing technology which can directly display the air flow speed on the LCD display. It is a perfect tool for sport events, wind measurement, navigation, HVAC, and other areas. Requires 3 x AAA 1.5V batteries (available separately). Size: 160 x 50 x 28mm. Weight: 118g. Accuracy: Wind speed: ±5%, +0.5. Accuracy: Temperature: ±2°C. Wind speed 0-30m/s 0.1m/s. Temperature: -10-50°C. Beaufort wind scale: 14-122°C, 0~12 level. Sampling rate 2/s Sampling rate is twice per second. Overload indication OL Shows " OL". MAX/AVG MAX/AVG Shows "MAX/AVG". Data Hold HOLD Shows "HOLD". Backlight BL Manually turn on or off. Auto power off 5mins Automatically power off after 5mins without operating Low battery 3.0-3.5V Shows low battery prompt when power is 3.0-3.5V. Wind chill notification windchill Shows"windchill". Battery: 1.5V(AAA) * 3(Not included). Size: 160 * 50 *40mm. Weight: 0.4KG. .