Now you can carry a weather station in your hand! Made by Flytec, a highly respected name in the Hang Gliding/Ballooning professions, the Alti Windwatch offers altitude, temperature, wind, and time information. Only 2 buttons to push, you can easily change or view the various measurement readings. To measure the wind speed, simply turn the Alti Windwatch in the direction of the wind, making sure the wind vane is freely spinning, then read the digital screen for the speed results. Altitude display range is 0-30,000ft (0-9,000m) with a resolution of 3ft (1m). Air pressure range is 26.60 to 32.49in Hg (900 to 1100hPa) with a resolution of 0.01in Hg (1hPa). Wind speed measurement from 0.1m/s to 40m/s (miles per hour or kilometers per hour also available), with a resolution of 0.1m/s and an accuracy of 4%. Temperature range is –20 to 55 degrees Celsius (Fahrenheit also available), with a resolution of 1 degree and an accuracy of 2 degrees. The Alti Windwatch weighs only 45g, with battery, and is water repellent. Comes complete with instructions and the CR2032 battery, which lasts approximately 2 years. Size: 3.9 x 1.6 x .7” (10.3 x 4.5 x 1.8cm). Made in Switzerland. Shipping weight 1 lb.