1. IN A SEALED ELECTRICAL CONTACT SET HAVING A PAIR OF FLAT CONTACT MEMBERS EACH WITH A SUBSTANTIAL PORTION OF ITS LENGTH EXTENDING WITHIN A PROTECTIVE ENCLOSURE, THE OTHER PORTIONS OF THE CONTACT MEMBERS EXTENDING OUTWARDLY OF THE ENCLOSURE, WITH A JUNCTION BETWEEN EACH CONTACT MEMBER AND THE ENCLOSURE AND WITH THE CONTACT MEMBERS HAVING OPPOSED CONTACTING PORTIONS IN THE ENCLOSURE, THE IMPROVEMENT COMPRISING: A STIFFENING RIB ON EACH CONTACT MEMBER EXTENDING THROUGH ITS JUNCTION INTO THE ENCLOSURE, EACH SAID RIB BEING OPERATIVE TO PREVENT SUBSTANTIAL FLEXURE OF THE PORTION OF ITS CONTACT MEMBER IS WHICH IT EXTENDS, SO THAT THE FLEXURE CHARACTERISTICS OF THE CONTACT MEMBERS ARE DETERMINED BY THE DISTANCE BETWEEN THE RIBS AND THE ENDS OF THE MEMBERS, RATHER THAN BY THE CHARACTERISTICS OF SAID JUNCTIONS.