This Atlas Trainman HO Scale AAR 70-Ton 9-Panel 3-Bay Open Hopper is based on common three-bay open hoppers used across the continent. This familiar hopper was an industry standard on many railroads since the 1930′s. It was adopted by the AAR as a recommended design, but fell out of favor by the mid-1950s. While offering greater capacity over cars with conventional flat sides, the original open hoppers created corrosive interaction between acidic coal and the car′s joints, leading to costly rebuilding programs. This hopper features an injection-molded body with applied plastic details where appropriate, removable coal load, smooth paint, crisp lettering, metal wheels and AccuMate(R) knuckle couplers. This AAR 70-Ton 3-Bay Open Hopper is one of many Trainman HO Scale freight cars.