To prevent impossible insertion of a printed wiring board or short- circuit with an adjacent electrode by engaging a polarity groove of the printed wiring board with a wedge type polarity protrusion provided with a suspension mechanism moving vertically by utilization of an elastic body and adjusting a position of the printed wiring board.

In an edge type socket connector 10 it is necessary to insert a printed wiring board 3 correctly, and precisely align a contact 11 with a print contact 12. Therefore, in the edge type socket connector 10, a polarity protrusion 1 engaged with a polarity groove 2 is wedge-shaped by thinning its upper part and thickening its lower part. Further, at the lower part of the polarity protrusion 1, a vertically moving suspension mechanism 4 is provided by utilizing an elastic body such as plate spring, for example. Thus, with a centering function through engagement with the polarity groove 2 of the wedge- shaped polarity protrusion 1 provided with a vertically moving suspension mechanism by utilizing the elastic body, in the case where displacement exists during insertion of the printed wiring board 3, alignment is made possible by horizontal moving force.