A longitudinal, generally parallelepiped electrical conductor bar, having a generally rectangular cross-sectional area having two sides and two ends, a substantially arc-like portion extending from one corner to an adjacent corner of that area, the arc-like portion defining two complementary sections, a first whose perimeter includes the arc-like portion, the two ends and one of the two sides, and a second whose perimeter includes the arc-like section and the other side, with parallel, elongate bores extending through the length of the conductor bar.