The Spokane and Inland Empire Railroad operated an electrified interurban network that had its core between Spokane, Washington and Coeur d'Alene, Idaho and developed tourist areas south of Spokane. In 1913, a Baldwin-Westinghouse steeplecab locomotive was procured for shunting tasks, which was given the number 502.
As is usual with interurbans, it was a DC locomotive with as many standard components as possible. Four Westinghouse 301-D-2, each with 100 hp, were used as traction motors, which were also used in large numbers in trams or interurban railcars.