A hand-held wind meter with lifetime accuracy. Pocket size convenience and simple to use. Rugged enough for sea-going us. Dual Range - 2 to 10 mph on low scale, 6 to 66 mph on high scale. See below for Metric Model and replacement balls. Dwyer Hand-Held Wind Meter 10008$17.95, 10/$169.50 Dwyer Hand-Held Wind Meter - Metric ModelSame features above. Dual Range (3.5 to 16 km/hr) on low scale, 8 to 104 km/hr on high scale. 10009$18.95, 10/$172.50 Replacement Balls for Dwyer Hand-Held Wind MetersPack of 3 10011A$12.95 Need more information? Please feel free to contact us at 1-800-592-6940 - Ask for Extension 547 or Internet Sales.