Mercury - MercMonitor NMEA 2000 Data Level 3 Gateway Premier Kit SmartCraft Display 79-8M0135619. Overview. The Mercury MercMonitor NMEA 2000 Data Level 3 Gateway Premier Kit (79-8M0135619) delivers the ultimate in SmartCraft functionality and performance monitoring. It features full SmartTow RPM control, Active Trim integration, and an NMEA 2000 Level 3 Multi-Engine Gateway, giving you total control and visibility over your engine data.. With SmartTow, you can launch and run your boat using pre