The Panzerjagerwagen with Panzer IV turret and long 7.5-cm KwK cannon, were an important innovation of the BP 44 armor train type. It was the armored pursuit car replace by the earlier pusher car. That now gave the train an effective means of against Russian tanks. In this instance, a program of new construction had been planned in 1944 by German Army: 8 BP 44 armored trains.