They are the smallest anemometers on the market, waterproof and highly accurate. Their ease of use and small size make them ideal tools for all outdoor sports where knowing the wind speed is essential. Powered by a lithium battery, weighing 30g, measuring 38x88x10mm, accuracy: ±3%. Performances provided: 1) instant wind speed in knots, km/h, mph, m/s, and maximum - 2) temperature from -40° to +8