A rest bar (10) for a double or multi-stranded rolling plant, adapted to cooperate with a rolling stand of said rolling plant, said plant defining a rolling axis, the rest bar comprising a motor (7), a reduction unit (8), a worm screw (6), a rolling guide (11), for guiding a material to be rolled into rolling cylinders (30) of said rolling stand, said rolling guide being fixed to the worm screw (6) so that, at an angular rotation of the worm screw (6) about its axis, the rolling guide (11) translates by a linear movement which is transversal to the rolling axis.