Electric power transmission system

An electric power transmission system comprising an overhead electrified metal trolley rail having a head and a foot separated by a vertical web integral therewith, the head being adapted to be gripped by hangers for supporting the rail, said foot projecting from opposite sides of the web and having flat upper contact surfaces separated by the web and substantially perpendicular thereto, a trolley shoe slidable along the rail and formed from an elongated block of electrical conducting material extending lengthwise of the rail, the upper portion of the block having a central trough therein extending from end to end of the block and receiving said foot of the rail with the lower portion of the trough spaced from the bottom of the rail, and the upper portion of the trough having integral longitudinal flanges projecting from its opposite sides inwardly toward each other above said foot of the rail, said flanges having flat lower contact surfaces engaging flat against said flat contact surfaces of the rail foot by gravity, the flanges supporting said shoe from the rail, and means secured to the shoe for electrically connecting a power take-off wire thereto.