Abstract: A cavity that crosses chambers and opens in an external wall is formed in a housing proper of a housing. A retainer is slidably fitted into the cavity, and linking parts that link chambers being divided into a front portion and a rear portion by the cavity are formed in the retainer. The linking parts are arranged in such a way that when the terminals are in a regular position in the chambers, the linking parts allow the retainer to shift in the sliding direction and the retainer is secondarily fixed to the terminals by this shift. The retainer is provided to be integral with the housing proper by means of a hinge.