As late as 1960 the B&O still rostered 231 class N-37 WWII emergency hoppers still with wood sides intact.
They also still had 575 class N-37A and 200 class N-37B which were these hoppers converted from composite to all steel construction. All of these cars had Duryea cushion underframes and were built by Bethlehem Steel Co. in 1943-44.
