The four-wheel electric locomotive, originally named WIEN No.1, was designed for electric traction tests on the Vienna municipal railway. Its mechanical part was manufactured by the Locomotive factory of the former Society of State Railway (StEG) in Vienna in 1906, electric outfit was provided by the Czech firm Krizik in Prague-Karlin. Krizik also made a design of the direct-current feeding system of the voltage 2×700 V. Because of unsuitable traction performance the locomotive did not prove well and after tests it was returned to Bohemia. After electrification of the Prague railway junction in 1927–1928 it was rebuilt for the voltage 1500 V and served for shunting at the Wilson railway station. Technical specification: axle arrangement Bo, feeding system: direct current 1500 V, original automatic vacuum brake for the train was put out of operation so that only hand securing brake was left. Original solution of the driving mechanism was application of driving twin-motors patented by Krizik.