Although a hermetic closing lid is nice - but has limited use if for the ground is not hermetically sealed .... Before the first filling, I washed the bowl with clean water - this has run through my bottom of the can.
So if you are looking for something that _wirklich_ is dense, then this socket is only suitable, who can live with the fact that it is at least relatively close, which it can define.
Otherwise, I have found nothing that would be objectionable