A front case 50 accommodates a substrate 30 on which female contacts 90 are mounted. The female contacts 90 are accommodated in a housing 70. From a rear portion 61 of a rear case 60, male contacts 80 protrude forward. The front protrusion 80a of each male contact 80 is provided inside a housing 62. When a housing 62 is fitted with a housing 70, each male contact 80 slides on and contacts leading ends 91a and 92a in the direction in which the housings are fitted.