Several months prior to the formation of Conrail, the Reading Company constructed their final group of hoppers--or any freight car for that matter--in their famed Reading Car Shops. The HTg hoppers were assembled from prefabricated kits supplied by Bethlehem Steel Car. These 45-foot, 12-panel, triple-bay hoppers had a cubic capacity of 3,487' and rode on flat-top Barber S-2 trucks with 36" wheels.

Unlike the other hoppers that the Reading had constructed in their shops during the 1970s, the HTg class did not have the famed Reading "speed lettering" scheme. Actually, they had no paint scheme in the true sense of the word. Only extra-large RDG reporting marks adorned the hoppers, a design elegant in its simplicity. The cars were assigned to the series RDG 483501-484600 and remained in the same series under Conrail, with CR replacing the RDG. A word of note about the CR series is in order since Conrail, as they so often did, mixed a few other classes into the series, making it almost impossible to figure out which cars were actually HTg's.

Like their smaller capacity cousin, the HTe, the HTg's were originally assigned to iron ore service between Bethlehem Steel's high-grade ore mine in Joanna, PA, on the Reading Company's old Wilmington & Northern Branch and the steel plants in Bethlehem. The HTg's were also placed into regular coal train service under both the Reading and Conrail.

Over 800 of these cars survived into the mid-1990's, still in original Reading Company numbers and paint, a reminder of Northeastern railroading prior to the Conrail era.