American Flyer Accessory 752A and 785 Coal Loader was considered an Operating Accessory. Operating Accessories were very interesting Gilbert pieces. Often times these models include complex mechanical and signalling components and were designed to make the train layouts even more realistic. All of these would have required additional power hook ups to American Flyer Transformers. They were different than regular accessories in that they usually were hooked up to power and had a push button or automatic track clip that made the operating accessory perform some task. In this case, the Sea Coaler would take coal and transport it to a waiting coal car.

American Flyer transitioned from a 3 part numbering system to a 5 part numbering system with the addition of an IBM computer for manufacturing and inventory tracking in the 1950’s.