ACF 3-Bay Center-Flow Covered Hopper 4-Pack - 3-Rail - Ready to Run - Premier -- BNSF Railway 402108, 402117, 402125, 402165 (Boxcar Red, white, Circle/Cros

The AtlasO Premier 3-rail O Scale ACF 3-Bay Center-Flow Covered Hopper is based on some of the most widely used cars in service since the late 1960s. Although covered hoppers had achieved widespread use by the 1950s, it wasn't until the following decade that they began to carry North America's grain harvest. Prior to the 1960s, U.S. and Canadian farmers sent their wheat and other grains to market in 40' boxcars. Loading and unloading was labor-intensive and time-consuming. All that changed with American Car and Foundry's (ACF's) introduction of the Center Flow covered hopper in 1961, followed the next year by Pullman-Standard's competitive PS-2CD covered hopper. Prior to the Center Flow, the typical covered hopper was little more than a coal hopper with a roof. Dry products such as salt were loaded through roof hatches and unloaded by gravity through doors in the floor. Like most freight cars of their era, these cars had a center sill. This support beam ran down the middle of the car b