Would you say its a hot water problem Nigel ? rectus is really for airlines not water maybe a combo of water and being hot has an adverse effect on the fittingI use hot water pal and have done for years and doesn’t affect my rectus fittings, if anything the hot water makes everything looser but I’m sure that’s just in my mind😂There is the genuine rectus fittings and the copies though, I’ve only ever used genuine off gardiner so can’t comment on the other ones but seen comments on various forums about the other type where the little centre insert doesn’t seal properly and leaks from grit and stops you connecting on properly too!has anyone checked if they have a temperature range for operation ?do you buy genuine Parker hannifin connectors ? there is a big difference in qualityDarran