An electrical connector forms electrical contact by tightening of a movable, electrically-conductive spiral around un-insulated wire or wires. The spiral coils around the wire multiple times and tightens on the wire(s) when either one or the other end, or both ends, of the spiral is/are rotated relative to the other. Various housing portions may be provided for connection to different portions of the spiral, to facilitate the tightening of the spiral and to cooperate with a latch/lock system to retain the spiral in tightened condition. Multiple spirals may be provided in one connector, including spirals that tighten around separate wires at opposite ends/side of the connector and/or in spiral ports extending transversely from a main spiral(s). Terminal ends or additional spiral units/ports may be connected to a given spiral, either permanently, semi-permanently, or detachably, for producing a wide variety of configurations and modular connection devices.