WeatherHawk Wind Meter Wind Tunnel Attaches overtop WeatherHawk wind meters to provide precise wind speed velocity in a specific direction Used with WeatherHawk wind meter models WM-100, WM-200, WM-300, WM-350, SM-18 and SM-19 (not compatible with SM-28) Meets NCAA Track and Field requirements Essential accessory for precision shooting, allows continuous cross wind readings Valuable tool for professional use such as chemical spraying and environmental monitoring