BHP

[Chip-mk1]

those cheap catch-cans usually have too small hosetails. Some have the larger kind now but the reall bad ones only have a 6mm internal.

If you get one like that, I'd recommend some low density foam be added to actually catch the vapour before it blows straight out the other end

All the ones I have seen have come with a selection of hosetails to allow you to select the outlet size.