This detailed Atlas HO Scale Master Gold Alco RS1 is modeled after one of the earliest roadswitchers produced. The RS1 was introduced by Alco in March of 1941 with the delivery of the first of two units to the Rock Island. Combining the accessibility of a switching locomotive and the higher-speed tracking of a road unit, the RS-1 started a revolution in locomotive design that was soon embraced by all of the major diesel-electric builders. Despite Alco′s own introduction of higher horsepower roadswitchers, the 1,000h.p. RS1 had a production span of 19 years (1941-1960) with 623 units. This Atlas model features a five-pole, skew-wound motor with dual flywheels, directional LED lighting, Accumate(R) magnetic knuckle couplers, accurate decoration and roadname-appropriate body details. This replica comes equipped with a dual-mode ESU LokSound Select sound and DCC decoder for operation on DCC and DC layouts (with limited sound capabilities on in DC operation). The RS1 is one of many Atlas HO Scale locomotives.