A connector includes a support (14) made of synthetic resin and constituting a first housing (10), a bolt (20) rotatably penetrating through the support (14), a seal ring (29) mounted between the supporting portion (14) and a head (22) of a bolt (20), a metal nut (36) embedded in the front surface of a second housing (30) and connecting the two housings (10, 30) by being threadably engaged with the bolt (20), and a stopper for preventing a threaded movement of the bolt (20) by bringing the metal parts into contact.