We make "Presetable Revolution & Time Counter" Model: RTC-K13 is a small electronic hand-held device that can be used to count Revolution & Time from mechanically rotating current meter.This RTC-K13 counter is used with water current sensor for determining velocities of flowing water in open channels and steams. Revolutions and Time is displayed on the three & half digit LCD display. Two terminals to connect the current meter sensor are provided on the front panel.The RTC-K13 offers (2)modes of operation,i.e. Revolution Mode as well as Timermode.