Paired matching connector for preventing wrongly matched

An anti-mismatching pair of first and second connectors are constructed such that the first connector (1) is of a male or female type and has two connective planes each having at least one restricted ridge (11,12). The second connector (21) is correspondingly of a female or male type and also has two connective planes each having at least one restricting groove (32,33) corresponding to the restricted ridge (11,12). The number and position of the restricted ridge (11,12) as well as those of the restricting groove (32,33) are designed such that the connective planes in each connector (1,21) have overall contours extending symmetrically with each other with respect to the center point (C) of symmetry lying between the connective planes. The one connector (1,21) mates only with the other connector (21,1), whether it is at its obverse position or at its reverse position relative to the other connector, so that a wrong connection of the one connector (1) with any other mismatching connector (22) is avoided.