Tachometer, Contact and Noncontact, Contact RPM Range 6 to 25,000, Noncontact RPM Range 6 to 99,999, RPM Accuracy +/-0.4 Percent, Working Distance 2 ft, Light Source Incandescent, Display 5 Digit LCD, Memory Last/Min/Max, Features Diode Detection, Measures Total Revolutions, Revolutions Per Minute, Surface Speed, Length, Makes Both Contact and Non-Contact Measurements, Calibration Certificate NIST