Abstract: In a sealing head for vacuum sealing a cap-shaped cover of relatively soft inelastic permanently deformable material with a sealing insert to a container of at least substantially rigid material provided with a beading on its outer face in the vicinity of its aperture, which sealing head has a flange plate, a head plate carrying a ring of pressure fingers projecting downwards and elastically yielding in a radial direction, which pressure fingers are surrounded by a rubber sleeve and also a steel sleeve placed over the latter, and a pressure plate carried by an axial shaft, held by the pressure fingers and displaceable inside these together with the shaft against the action of a spring, the improvement comprising the head plate together with the pressure fingers carried by it being displaceable relative to the flange plate by a limited amount on the shaft against the action of resilient means and enclosed by a rigid external shell connected to the flange plate and forming underneath the free end of the pressur