Atlas Master 20007004 - 50' Berwick Box Car Seaboard System (SBD) 140884 - HO ScaleAtlas Master 20007004 50' Berwick Box Car Seaboard System (SBD) 140884 HO Scale In 1972, Berwick Forge & Fabricating, of Berwick, Pennsylvania began producing modern 50 sliding door box cars which featured their new corrugated non terminating sine wave ends. Initially sold to over 35 railroads across the nation, these box cars were an unfortunate casualty of the economic recession of the late 1970s and Berwick was forced to stop production in 1982.