O Scale Flatcar
Flatcars hold an important place in railroad history: they were the very first type of rail car used by the railroad industry. Thanks to their simple, flat-deck design, flatcars carried all sorts of freight. For that reason, the design didn’t change much over time. Today, there are several variants of flatcars, including spine cars, centerbeams and well cars. Even so, the basic flatcar is still riding the rails to this day, carrying equipment, machinery, oversized loads, pipe, steel beams and more.
Flatcars are used to ship freight that is too tall, wide, long or heavy to be shipped on another rail car type. These are referred to as “dimensional loads” or “hi-wide shipments” and include things like heavy construction machinery, military equipment, farm equipment, industrial parts, pipe, steel beams and rails for railroad tracks.
Source UP Website