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The Seaboard Air Line was the only E4 purchaser; this is locomotive #3003 and another at Richmond, Virginia in 1939.
The EMD E4 was a 2,000 hp, A1A-A1A passenger train-hauling diesel locomotive built by the General Motors Electro-Motive Division of La Grange, Illinois.
The E4 was the fifth model in a long line of passenger diesels of similar design known as EMD E-units.