Abstract: A gasket is manufactured by a method which comprises applying heat to selected localised areas of a piece of sheet steel so that the structure of the steel is softened only in those areas. An opening is formed through said piece of sheet steel, the opening extending around a closed path in the sheet which passes through said softened areas. The opening has connecting webs extending across it at the softened areas. The method also comprises pressing said webs so that slots are formed in the top and bottom of each web, the slots connecting with the opening on both sides of the web. The method also comprises filling said opening and slots with resilient material which also forms sealing beads extending along said path and projecting from said opening and slots on both sides of the sheet.