This F-7 B unit locomotive was built in December 1952 for Alaska Railroad. Three  A units, as well as two additional B units, were produced and delivered at the same time. On the Alaska Railroad, all F-7 A units carry even numbers and all B units carry odd numbers. F-7 A # 1500 received this paint scheme in the 1980s and is currently on display at the Alaska Museum of Transportation & Industry. F-7 B # 1503 received this paint scheme at the same time and was sold to National Railway Equipment in 2006, who sold it to the Royal Gorge Route Railway.