Abstract: An improvement is provided in an electrical connector system which includes a connector block of insulating material having a plurality of pin receiving openings for positioning a plurality of terminal pins therein by an interference fit. At least some of the openings each are generally rectangularly shaped and include inwardly directed pin engaging projections located in diagonally opposite quadrants of the rectangular opening. The invention contemplates that the connector block may have a series of the openings in a closely spaced row. The diagonally opposite quadrants in which the projections are disposed are at the same respective locations in each opening along the row.