Tachometer 2 in 1(Contact Type 0.5~19,999RPM & Photo Type 5~99,999RPM) (DT 6236B)

Microcomputer and advanced semiconductor laser 
technology are used for fast and highly accurate measurement
Photo/Laser type: The non -contact meter analyses light or 
laser beam reflected off a rotating object into the meter
and convert into RPM value, the laser reflection is eyeable 
for easy object locating
Touch type: Supplied with an optional interchangeable rubber
cone tip for shaft rotation measurement and rubber wheel for 
surface speed measurement, reading switchable as RPM, 
meters/min or feet/min
Memory button recalls the last, minimum and maximum values 
during measuring period
For more details please refer datasheet.