SBK meaning in Regional ?

The South Brooklyn Railway (reporting mark SBK) is a railroad in the New York City borough of Brooklyn. It is owned by the City of New York and operated by the New York City Transit Authority. Its original main line ran parallel to 38th Street from the Upper New York Bay to McDonald Avenue, and south on McDonald Avenue to the Coney Island Yards, mostly underneath the former Culver Shuttle and the IND Culver Line of the New York City Subway.

Parts of the original line still exist. The section between the BMT West End Line's Ninth Avenue station and its interchange yard at Second Avenue and 39th Street is still open. The section under the IND Culver Line has been paved over. Today, it runs only from the 36th–38th Street Yard in the east to the South Brooklyn Marine Terminal in the west.