A kit for making a connector permitting alternative interconnections between individual conductors of two parallel, planar arrays of conductors includes an insulating body with means to locate contact parts on opposite faces for alignment with chosen conductor to provide the alternative interconnections. The contacts are of three basic types comprising respectively a conductor engaging portion integrally joined to either a bus portion, a bus gripping portion or another conductor engaging portion. The locating means includes recesses on opposite faces communicating by contact receiving sockets extending between the faces and bus receiving channels extending between recesses on the same face.