S-Motor was the class designation given by the New York Central to its ALCO-GE built S-1, S-2, S-2a and S-3 electric locomotives. The S-Motors hold the distinction of being the world's first mass-produced main line electric locomotives with the prototype #6000 being constructed in 1904. The S-Motors would serve alone until the more powerful T-motors began to arrive in 1913, eventually displacing them from main line passenger duties. From that point the class was assigned to shorter commuter trains and deadhead rolling stock between Grand Central Terminal and Mott Haven coach yard. Some examples, including the prototype later renumbered #100, would serve in this capacity through the Penn Central merger in 1968, only being retired in the 1970s as long distance passenger traffic to Grand Cent