Tachometer for monitor the speed of marine diesel engine. Every boat need to install one PC,  If you are interested in pls take a look. 

*Temperator of water monitor
*Temperator of Oil monitor
*Pressure of Oil monitor
*Monitor the speed of marine diesel engine

1.A micro-computer/computer/contract tachometer, designed to be used with ships, automobiles and other instruments, has the advantages of stable performances and convenient use.

Its main technical data include:   

                          1. Input voltage: 8 ~ 32V

                          2. RPM: 0 ~ 9999RPM

                          3. Display: high brightness digitron