Mercury - 5-Way J-Box Kit with Weather Caps SmartCraft Network Hub 98-8M0165557. Overview. SmartCraft networks work best when the layout is clean and each device has a proper connection point. The Mercury 98-8M0165557 5-Way J-Box Kit gives you a tidy hub for expanding or organizing a SmartCraft system, making it easier to add gauges, sensors, or modules without messy adapters. With three included weather caps, unused ports stay sealed and protected, keeping the network stable through long season