This Tachometer provides both contact (0. 5 to 19,999 RPM) and non-contact (10 to 99,999 RPM) RPM measurement functions for use in virtually all applications. Laser guided non-contact measurements up to 6.5 ft. (2 meter) away for added safety and convenience. Comes with wheels for linear surface speed (0.2 to 6560 ft. /minute; 0.05 to 1999.9 m/minute) or RPM measurements, 4 AA batteries, 23 in. (0.6 m) reflective tape, carrying case, and user manual. Includes certificate traceable to NIST.