Electric apparatus for a medium-voltage, high-voltage or very-high-voltage power line, in particular a disconnector having bars, comprising: - a conductive upstream portion and conductive downstream portion, - a pair of retractable elements (50, 50') made from at least one electrically insulating material, the retractable elements (50, 50') being configured to pivot about a fixed axis with respect to the downstream portion, characterised in that the apparatus further comprises: - a pair of mobile conductors (30, 30') mechanically and electrically connected to the upstream portion, the mobile conductors (30, 30') being mounted movably with respect to the upstream portion, between a closed position of the electric apparatus in which the mobile conductors (30, 30') are in electrical contact with the downstream portion and an open position of the electric apparatus in which the mobile conductors (30, 30') are at a distance and electrically insulated from the downstream portion, - elements (20, 22, 24, 22', 24') for driving the mobile conductors (30, 30'), in that the mobile conductors (30, 30') are mechanically connected to the retractable elements (50, 50'), in that the drive elements (20, 22, 24, 22', 24') are configured to both pivot the retractable elements (50, 50') with respect to the downstream portion and move the mobile conductors (30, 30') between the closed position and the open position, and in that the mobile conductors (30, 30') and the retractable elements (50, 50') of each pair are arranged substantiallysymmetrically, via plane symmetry, with respect to the same plane. - a conductive upstream portion and conductive downstream portion, - a pair of retractable elements (50, 50') made from at least one electrically insulating material, the retractable elements (50, 50') being configured to pivot about a fixed axis with respect to the downstream portion, characterised in that the apparatus further comprises: - a pair of mobile conductors (30, 30') mechanically and electrically connected to the upstream portion, the mobile conductors (30, 30') being mounted movably with respect to the upstream portion, between a closed position of the electric apparatus in which the mobile conductors (30, 30') are in electrical contact with the downstream portion and an open position of the electric apparatus in which the mobile conductors (30, 30') are at a distance and electrically insulated from the downstream portion, - elements (20, 22, 24, 22', 24') for driving the mobile conductors (30, 30'), in that the mobile conductors (30, 30') are mechanically connected to the retractable elements (50, 50'), in that the drive elements (20, 22, 24, 22', 24') are configured to both pivot the retractable elements (50, 50') with respect to the downstream portion and move the mobile conductors (30, 30') between the closed position and the open position, and in that the mobile conductors (30, 30') and the retractable elements (50, 50') of each pair are arranged substantiallysymmetrically, via plane symmetry, with respect to the same plane. - a pair of mobile conductors (30, 30') mechanically and electrically connected to the upstream portion, the mobile conductors (30, 30') being mounted movably with respect to the upstream portion, between a closed position of the electric apparatus in which the mobile conductors (30, 30') are in electrical contact with the downstream portion and an open position of the electric apparatus in which the mobile conductors (30, 30') are at a distance and electrically insulated from the downstream portion, - elements (20, 22, 24, 22', 24') for driving the mobile conductors (30, 30'), in that the mobile conductors (30, 30') are mechanically connected to the retractable elements (50, 50'), in that the drive elements (20, 22, 24, 22', 24') are configured to both pivot the retractable elements (50, 50') with respect to the downstream portion and move the mobile conductors (30, 30') between the closed position and the open position, and in that the mobile conductors (30, 30') and the retractable elements (50, 50') of each pair are arranged substantiallysymmetrically, via plane symmetry, with respect to the same plane.