After WWII, US railroads were increasingly called upon to haul new and unique "modern" products over long distances. In response, American Car and Foundry (ACF) designed a tank-type covered hopper car. The cylindrical shape created a better weight/volume ratio; plus, the elimination of interior ledges, combined with hatches and outlets placed along a center-line, led to ACF's trademark "Center Flow" hoppers. Through the 1960s the Cylindricals became omnipresent on our nation's railroads, with many styles of hatches and outlets devised according to needs. Because the cars were compartmented, various different loads could be carried in a single unit, and some had aluminum construction to further reduce weight. Here was a "Freight Car for the Future," ready to transport sugar, cement, sand, salt, fertilizers, many types of grains, coke, starch, feeds, chemicals and plastics!

Unless otherwise indicated, all hoppers are equipped with Micro-Trains roller bearing trucks and Magne-Matic couplers.