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This one is here for documentary purposes, it may never be for sale as a particular British filter maker may well turn around and sue me.
Anyhow, their 75mm filter system doesn't have an adapter ring for lenses with 48mm threads like the Leica Elmarit 28mm (version 2, pre aspherical).
If it were to ever be made it would be machined locally out of aluminium.
The design is fully procedural meaning any other missing lens size can be accommodated.