Mercury - Extension Harness 2-Pin Excitation and Ground 84-8M0176939. OverviewThis ten-foot harness gives you the extra reach you need when the rig center and isolator aren't close together. It keeps things simple-just a clean way to run excitation and ground without stretching or forcing wires around tight corners. The longer run also makes it easier to route the harness in a way that actually makes sense when you open the rigging bay later. It's a small piece, but it helps the whole setup feel