Fast Response Probe. Air Flow Volume Instant / Avg / 2/3 Vmax Flow Measurement. Velocity m/s, ft/min, knots, km/hr, mph. Data hold & Maximum / Minimum function. Manual data memory and read function (10 x 99 sets). LCD triple display. Auto power off function ON / OFF Time setting. Backlight function ON / OFF Time setting. Snake telescoping probe. Learn More