The Pocket Wind Meter is very accurate, very tough and very affordable. It features a large liquid crystal display which is easy to read and offers three operating modes â€“ wind speed, average wind speed, and maximum wind speed. The display units can be changed at any time, with choices to suit a wide variety of applications (knots, meters per second, kilometers per hour, miles per hour or feet per minute). To measure wind speed, the meter relies on a precision ultra light anodized aluminum impeller mounted in jewel bearings. This impeller yields high accuracy (within 3%) and a low startup speed (0.3 M/S). The meter is waterproof and floats. The hard case slips on and off easily and protects the display and all moving parts from damage. Unit also displays Temperature.