Headlamp for vehicles with a shielding housing for the ballast unit of the discharge lamp

A contact device fits on an electronic circuit's (22) earth connection element (ECE) (27) leading out of a casing (21). Protruding from the casing, the ECE is designed so that it maintains an electrically conductive contact with the casing's base wall (26). The ECE also forms an earth contact pin with a widening section (28) near an aperture in a reflector for retaining a lamp.