Included are terminal metal parts mounted on ends of electric wires, a housing housing the terminal metal parts at a housing completion position thereinside and to be inserted and fit into a counterpart fitting portion headed by a tip, a terminal locking member mounted on the housing from outside along a direction crossing an insertion direction of the housing to the counterpart fitting portion and locking the terminal metal parts as they are at the housing completion position at a mounting completion position with respect to the housing, and a front holder causing the housing to be inserted headed by the tip and locking the terminal locking member at the mounting completion position.