Atlas 20006903 Master Plus HO ACF 5250 4-Bay Covered Hopper, Amoco #6221Atlas 20006903 Master Plus HO ACF 5250 4 Bay Covered Hopper, Amoco #6221 Part Number: 840245212147 Description Atlas Master Plus HO ACF 5250 4 Bay Covered Hopper, Amoco #6221 Atlas Item #: 20006903 ACF introduced the 5250 cubic foot size covered hopper in 1964, and has since built nearly 20,000 cars. Most of the cars were equipped with pneumatic outlets and eight 20" round hatches for use in transporting plastic pellets. In addition to the plastics