A ZIF type IC socket consists of a base housing assembly that accommodates numerous contacts, and a cover housing assembly that can slide over the base housing assembly. The cover housing assembly is caused to move in relative terms by inserting a plate-form tool into tool insertion holes respectively formed in a metal supporting plate on the side of the base housing assembly and a metal supporting plate on the side of the cover housing assembly, and rotating this tool. The action points of the tool insertion holes contacted by the tool are formed as circular-arc-form projections. Accordingly, the force of the tool can be transmitted to the base housing assembly and cover housing assembly without causing indentation or damage, etc., of the tool insertion holes, so that a highly durable ZIF type socket can be obtained. |