*Possibly EPDM.neoprene (or whatever it actually is*) as used on Hep2o & speedfit tap connectors.
Fibre because as it gets wet it expands Like hemp does - before the H+S police found one microbe growing on it Nylon manufd. because they can be made 1000 for 1p in ChinaThanks, I guess fibre is the winner.
If I could maybe just ask a few questions just to enhance my understanding.
Why is fibre prefarable?
Why are nylon washers manufactured?
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