Thinking bigger is better I bought the 3/4 inch outside tap from
Toolstation. Item 32002. The 3/4 refers to the bsp thread size
conecting to the backplate.

I want to use hozelock type fittings but cannot work out how to connect
to the outlet which has a male thread.
A 3/4 inch hozelock connector is too small
A 1 inch hozelock conector is too big
It does not appear to be a bsp thread as the pitch is too fine.

Is there a standard for these tap threads I should know?