Features:Dual use for non-contact contact testing on your needs.Have 4 different connecting head used for contact measuring.Wide measuring type: can test rotational speed(RPM), counter rotating(REV),frequency(Hz),surface speed(m/minute; inch/min; feet/min; yard/min and length(meter, inch, feet, yard).High resolution ratio and 5-digit backlight LCD display.Latest laser targeting technology.All 30 data storage: 10 maximum/ minimum/instantaneous measuring data.Wide measuring range: non-contact way--2 to 99999RPM; contact way--2 to 20000.Sampling time is just 0.5 sec.Extensive usage: usually can be used in the field of motor, electrical fan, paper making, plastic industry, chemical fiber, washing machines, car making etc.