Abstract: The joint packing, especially for sealing two abutting flanges or surfaces, comprises a sealing ring core composed of a slightly deformable metal and opposing plastic deformable soft sealing seats. The sealing ring core has chamber-defining formations on its upper side and lower side outer edge (and inside edge) running circumferentially between which the soft sealing layers are pressed when the sealing forces are applied thereto. The chamber-defining formations have a bulged rounded cross section. The surfaces between the chamber-defining formations on the outside edge and the inside edge are smooth and arched.