Through the special underhead geometry the jointing forces and the joining work can be reduced, because the punch side sheet does not come into contact with the underside of the rivet head until quite late, the
8. The RTV organopolysiloxane composition as defined by claim 1, wherein said at least one tin catalyst (4) comprises a compound of the formula: ##STR13## in which R1and R2, which are identical or different, are each a C1-C12alkyl radical, a C1-C12alkoxy radical, a C2-C12alkenyl ...