This detailed HO Scale Atlas Master Silver Alco S2 is based on the 1,000-horsepower switchers introduced by the American Locomotive Company (Alco) in 1940. With over 1,500 locomotives produced through 1950, the long-lived line of locomotives used turbocharged 539-series prime movers. The Alco S2 features accurate body panels, horizontal or vertical shutters as appropriate, accurate decoration, roadname-appropriate details, LED lighting and plenty of applied details. This Alco S2 model has a five-pole, skewed-armature motor, dual flywheels, a heavy die cast chassis and AccuMate(R) knuckle couplers for smooth, reliable operation. It has a built-in 8-pin DCC decoder socket for easy decoder (sold separately) installation when you're ready.