The Dwyer WIND METER-MPS Portable Wind Meter, MPS Scale is used to indicate wind speed and is ideal for yachtsmen, outdoors-men, and farmers. The WINDMETERMPS is direct reading, no calculations, hold meter at eye level and back of unit to wind. The WINDMETERMPS's white ball in tube indicates wind speed. Meter has two scales for maximum accuracy and easy reading - low, 2-10 and high, 4-66 mph range. The WINDMETERMPS is for high range, cover hole with finger. The WINDMETERMPS is pocket size, sturdy plastic, and has case.