Just wondering, do 'The Trade' fit these rings ?
https://www.wras.co.uk/consumers/resources/interpretations_and_advice/backflow_prevention/b20/
Seems sensible but prevents someone washing their hair over the bath.
https://www.wras.co.uk/consumers/resources/interpretations_and_advice/backflow_prevention/b20/
Seems sensible but prevents someone washing their hair over the bath.