Where would be a good place to get hold of imperial john guest fittings? Tried the local plumber's merchant to no avail and Wickes etc just seem to do large plumbing sizes rather than the CO2 ones. The web doesn't turn up much either apart from this:
Placed an order for a female coupler, if that doesn't fit I'm going to have to cobble together some Frankenstein's monster of reducers and convertors...