For greater adaptability, the Extech RPM33 measures revolutions per minute using both contact (2 to 19,999 rpm) and non-contact (2 to 99,999 rpm). Safely record laser-guided non-contact RPM measurements from up to 500 mm (1.6 feet) away. The RPM33 is displayed on a big five-digit backlit LCD. Memorize and recall ten data sets with four parameters (measurement, maximum, minimum, and average). The unit includes a contact wheel for measuring linear surface speed (0 to 1999.9 meters per minute; 0.2 to 6560 feet per minute) or RPM, a 9-volt battery, reflective tape, a carrying case, and a user manual.