A single-pole or multi-pole device for low-voltage systems, in particular a circuit breaker or a disconnector, which comprises: an outer casing containing for each pole at least one fixed contact and at least one mobile contact that can be coupled to/uncoupled from one another; a rotating element that comprises a shaped body made of insulating material comprising at least one seat for each pole of said switch, said seat being designed to house at least one mobile contact of a corresponding pole; a control mechanism operatively connected to the rotating element for enabling movement thereof; and one or more elements made of ferromagnetic material set in a position corresponding to at least one portion of the inner surface of said at least one seat of the mobile contact.