Any rotating surface may be touched by the cone convex tip, funnel concave tip, or speed wheel for instant results. Tachometer displays revolutions per minute (RPM) from 10.000 to 99,999 (resolution 0.001, 0.01, 0.1, 1). In addition, it reports results in feet per minute 3.0000 to 30,000, yards per minute 1.000 to 10,000, and meters per minute 1.000 to 9999.9 (resolution for all three is 0.0001, 0.001, 0.01, 0.1 depending on the revolutions displayed). Unit is designed to measure centrifuges, pumps, rollers, shafts, gears, motors, and moving surfaces. For accuracy, see chart.