These Canbus driven gauges operate on either Smartcraft or NMEA 2000 systems, just select the system on your engine. The LCD on the Tach and Speedo display all available data and alarms, while 2" gauges receive data from Tach via a private network. The Tach is required on all systems to drive the other gauges. Connectors are IP67 waterproof and gauges are dry dry nitrogen filled to minimize fogging. Red LED automotive style dimmable backlighting