Mercury - NMEA 2000 Power Harness Fused Backbone Power Lead 84-8M0114012. Overview. A stable NMEA 2000 network starts with clean, dependable power. The Mercury 84-8M0114012 Power Harness gives you a fused, overmolded connection that plugs directly into the backbone and keeps every device on the network supplied with the voltage it needs. It's simple, sturdy, and built for the kind of wet, noisy, vibration-prone spaces where most marine wiring lives.. Key Features. Backbone Power Feed - Provides