This 1778 cubic foot capacity drop-end mill gondola with ASF Ride Control trucks was built for Denver & Rio Grande Western, and was designed to haul finished structural steel shapes and other bulky loads featuring drop ends that allowed the gondola to carry loads longer than the car. D&RGW was formed in 1870 and operated the highest mainline railroad in the United States through the Colorado Rockies at an altitude of 10,240 feet.