A tap changer for connection to a regulating winding of a rated regulation voltage is provided. The tap changer having a linear tap selector having at least one current collector and a linear arrangement of fixed contacts. Tap changer further includes a shielding structure arranged to shield the tap selector from an external electrical field. The shielding structure includes: a first shielding part arranged to be electrically connected to a current collector; and a second shielding part formed at least partly by the fixed contacts. The first and second shielding parts are separated so that the distance between the first and second shielding parts reaches or exceeds the rated regulating voltage insulation distance of the tap changer.