Mercury - CAN Data Harness (10-Pin, No Resistors) 20-Foot SmartCraft Lead 84-879969T20. Overview. Long SmartCraft runs on bigger boats need room to breathe, and this harness delivers it. The Mercury 84-879969T20 CAN Data Harness adds twenty feet of non-terminated SmartCraft cable, giving you the reach to route the data line cleanly through consoles, bulkheads, and deep rigging channels. It carries CAN P, CAN X, and CAN H signals through the standard yellow 10-pin plug, making it a reliable choic