A closure system comprising a filler neck (1) and a guide sleeve (2) arranged within the filler neck (1), as well as a closure cap (3) which can be inserted between the filler neck (1) and the guide sleeve (2) and can be fastened to the filler neck (1) by ...

The lid has a cap-like closure body (1) screwable on a filler neck, and a retainer comprising a lip seal (10) for sealing an annular gap between the neck and the body. An insert element (4) is fixed into the body through an open lower side of the body. The...