The H45 class of covered hoppers were built in two groups by ACF in 1966 as PRR 259751-260000 & PRR 260776-260870. 163 cars of the PRR series 259751-260000 carried their PRR number to Conrail and were renumbered into the CR 888521-890851. The wide number range is due to cars being renumbered around other cars joining the fleet. 80 cars from the same PRR series became PC 888000-888247 and then CR 888000-888247. 68 Cars from the PRR 260776-260870 series carried their PRR number to CR and were renumbered into CR 891086-891108. 25 cars of the same PRR series became PC 888248-888340 and then CR 888248-888240. Cars are rated at 100 tons, 4600 cuft & are 57 ft long.