The Chicago, Rock Island & Pacific acquired 5,500 Fowler-clone boxcar from several builders between 1913 and 1915. After construction, few significant changes occurred to the cars before retirement in the late 1940s and early 1950s. About 600 members of the class were rebuilt as the 77000 and 79000 class stock cars after World War II.

This model represents an example built by Pullman during the 1940s.

The Denver & Rio Grande acquired 1,500 of these cars (numbers 66000 through 67499) from Pullman-Standard in 1916. These were copies of the Rock Island cars above. Through merger, these cars went to the Denver & Rio Grande Western in the 1920s. During the 1930s, the majority were converted from Westinghouse K-1 brakes to AB brakes.

This model represents a car during the 1940s.

The Minneapolis & St. Louis acquired 500 Fowler-clone boxcars from Bettendorf in 1916 (numbers 18000 through 18998 - even numbers only.) These were copies of the Rock Island cars above. These cars experienced few significant changes before retirement in the late 1940s.

This model represents a car during the 1930s.

Over the 1920s, the St. Louis - San Francisco (Frisco) acquired 6,500 composite boxcars to American Car & Foundry's Howe Truss design. The Howe Truss cars were designed in response to dissatisfaction with the 1923 American Railroad Association single sheathed design. In particular, the AC&F design made use of standard structural steel in lieu of custom stamped framing. This change both reduced costs and prevented rust in inaccesible areas. The AC&F design outsold the ARA design by approximately 10 to 1, leading it to be dubbed by some as the "Defacto" standard boxcar. Frisco rebuilt several hundred cars with steel sheathing in the 1950s. As steel cars, these remained in service into the 1970s.

This model represents an unrebuilt car during the late 1940s.

In 1926, the Missouri Pacific acquired 2,750 examples of the AC&F "Defacto Standard" boxcar. About half were rebuilt with steel sides in the 1950s. Rebuilt cars lasted into the 1970s while unrebuilt cars were retired in the 1960s.

This model represents an unrebuilt car during the early 1950s.

OVer the 1920s and 1930s, Canadian National acquired nearly 10,000 examples of the "Defacto Standard" boxcar. All cars were modernized by Canadian Car & Foundry in the 1950s, receiving steel doors, AB brakes and other modern features. However, the cars received new wood sheathing at that time instead of being converted to all steel cars. These cars remained in revenue service into the late 1970s.

This model represents a rebuilt car during the 1950s.

Following World War II, the Rock Island rebuilt 600 of the obsolete Fowler Clone boxcars into stock cars. The coverted stock cars remained in service into the 1960s.

This model represents an earlier rebuild in the late 1940s.