NSA operates a fortnightly service between Houston, Port Everglades and Puerto Rico. Rickers-Linie, which focuses on project, breakbulk and heavy-lift cargoes, will also serve as general sales agent for NSA in North America. NSA operates the National Glory, a U.S.-flag ship with capacity of 570 twenty-foot equivalent units and 13,800 deadweight tons, in the Jones Act trades. It is the only vessel in the domestic Puerto Rico trade that was built to carry both containers and breakbulk/project cargoes, both above and under deck, the lines said. Rickmers-Linie operates a 10-vessel, round-the-world Pearl String service, connecting 16 ports in Europe, Asia and the Americas. It calls fortnightly at Houston, where Puerto Rico-destined cargo is relayed directly the National Shipping vessel.