Waterproof, floating, electronic pocket-sized wind meter with adjustable scale for mph, m/s, KT, Km/h, fpm. Provides wind speed, average speed, and maximum speed readings on LCD display. Slip-on hard case protects it from damage. Anodized aluminum impeller yields accuracy within 3% and can be replaced if damaged. 400 hour battery. (4.6 X 1.8 X 0.7 in. ) 1 year warranty!