Chris Hogg wrote:

It's not got some sort of flow controller hidden in the fitting, has
it, along with the pressure reducer?

couldn't see one inside the cavity wit the spring, but didn't have any
suitable tools with me.

I have one somewhere, taken off
an inherited hosepipe. Damn nuisance. It's supposed to stop the flow
if it thinks that the flow is too high, i.e. that the hose has split
or the spray head has come off.

I've ordered a pressure gauge, was going to collect it and check this
evening, but didn't realise toolsatan are closing at 5pm these days.