A miniature high density connector including a thermoplastic insulating body having contact cavities for the insertion, the positioning and the retention of electrical, optical or electro-optical contacts, a back plate having clips for the locking of the contacts into the contact cavities of the insulating body, a receptacle shell constituting an interface element for coupling with a complementary mating connector having a flange for the assembly and the retention of the insulating body and the back plate in the receptacle shell, the back plate being movable and including a projecting dimple located on the side wall, making possible its locking into the receptacle shell.