Tim+ was thinking very hard :
I think it is just a €œstandard€� Hoselock type connector. Theyre made by
many people these days though and there will be small differences in
€œnon-critical€� dimensions.

I have several of the usual size, one which is bigger and almost
tightens.

Why not buy a brass one? Unlikely to break again and probably has a larger
internal bore.

I have a brass Hozelock version which has a too small internal thread.