Model NO.: HT-81 Accuracy: 1mm Horizontal Line: 1 Vertical Lines: 4 Resolution: 1ft/Min 0.01m/S 0.1km/S 0.1of(0.1oc). Measuring Range: Ft/Min 196-4900ft/Min M/S 1.00-25.00m/S Km/H 3.6-9