Abstract: Electrical connectors each having one row of electrical terminals, are joined together in end to end relationship by slugs formed integrally with end walls of the connectors. Lead receiving portions of the terminals of both of the connectors are loaded with electrical leads, which extend therefrom in the same direction. The slugs are then removed so as to separate the connectors. Dovetail cross section ribs on a side wall of one connector are then slid into complementary grooves in a side wall of the other connector so as to couple the connectors together in back to back relationship, with the leads projecting from opposite sides of the composite two row connector so provided. The invention enables the leads to be loaded into the connectors by means of a lead loading apparatus which is capable of loading electrical connectors only from one side thereof.