a connecting element of thermoplastic material is provided for connection to a hollow body , such as an insert for a fuel tank . the connecting element or insert has the form of a component which lines a connection opening of the hollow body and / or forms a seat for a connection element . the connecting element is produced by press shaping a laminate of thermoplastic material , preferably one which has low permeability for hydrocarbons by including at least one barrier layer in the laminate . the press shaping is carried out between two mating platens , preferably male and female mold portions . the laminate may be formed by co - extrusion of a multi - layer preform , preferably in the shape of a tube having oppositely disposed walls , which are pressed against each other in the press shaping step .