Abstract: The invention comprises a lever ring to be connected to a body (20) by means of a seam and for receiving a closure layer (1) that has been connected by means of sealing onto the edge and which bridges an inner space of the lever ring and, in the seam-connected condition, closes the body (20), wherein the lever ring comprises a continuous flat web (3a, 3b, 3c), which radially outwardly changes into a lid rim (2) of the lever ring, a continuous groove (n1, N2, N3) extending between the lid rim and the flat web, the flat web is suited for connecting the edge of the closure layer by means of sealing and extends at an angle (?1, ?2, ?3) differing from zero with respect to the plane of a closure layer (1) being connected by means of sealing in this fashion the holding force on the flat web is increased.