The J Nassau Street Local/Express and Z Nassau Street Express (displayed as Jamaica Local/Express on the R160 cars) are two rapid transit services in the New York City Subway's B Division. Their route emblems, or "bullets", are colored brown since they use the BMT Nassau Street Line in Lower Manhattan.
The J operates at all times while the Z, operating internally as its rush hour variant, operates six trips in the peak direction on weekdays; both services use the entirety of the BMT Archer Avenue Line, the BMT Jamaica Line, and the BMT Nassau Street Line between Jamaica Center in Jamaica, Queens and Broad Street in Lower Manhattan (via the Williamsburg Bridge between Brooklyn and Manhattan). When the Z operates, the two services form a skip-stop pair between Sutphin Boulevard–JFK Airport and Myrtle Avenue–Broadway, and run express between that station and Essex Street, bypassing four other stations. At all other times, only the J operates, serving every station on its entire route.