PS-2 TWO BAY COVERED HOPPER - LATE VERSION - BNSF #405648 - GRAY - HO Scale. Before the development of the Pullman Standard PS-2, it was common practice to transport granular materials such as feed, cement, and sand in bags stacked inside boxcars. This meant that valuable space was lost, and while the bags could easily be unloaded for smaller customers, the process would be cumbersome for customers requiring bulk deliveries. Pullman Standard changed all this in the late 1940s by providing a car that could be top-loaded, filled to its maximum capacity, and emptied from underneath, effectively revolutionizing bulk transportation. Bachmann’s newest PS-2 Hopper is based on later examples of this car seen from the 1970s through to the present day, which primarily hauled cement and sand for both revenue customers and in maintenance service. Finished in Silver Series® quality, the Bachmann PS-2 Two-Bay Covered Hopper features authentic details, a see-through roof-walk, E-Z Mate® Mark II knuckle couplers and metal wheels.