A plug-and-play hub with robust 100-megabit switch for high-speed data-sharing of multiple HDS, LCX, LMS, and GlobalMap products with 5-pin ethernet connectors across an onboard network. New box design emits less VHF radiated energy than its predecessor, NEP-1, thus eliminating VHF interference. Will connect up to 4 compatible head units per expansion module. Waterproof expansion ports resist corrosive marine environments. Unused expansion ports are capped till future expansion. Links with other Expansion Port-1 modules for added expansion.