High Precision Contact Tachometer (461891)

The 461891 is a contact Tachometer. 
Surface wheels measure contact surface speeds
(10 to 9,999 rpm) of rotating objects. 
The memory button holds last reading and recalls
min/max readings display. 
Complete with wheels for linear surface speed 
(0.2 to 6560 feet/minute; 0.05 to 1999.9 meters/minute) 
or RPM measurements. 
Comes with cone tip, flat tip and spare wheel for
surface speed measurements, four AA batteries, 
carrying case, and user manual.
For more details please refer datasheet.