Yup, measure the OD if the old tube and the new. It could be smaller, it could not.
The only other thing that i can think of, for this problem
Did you ever measure the OD of their pipe?
And just to be clear, as I said before, these fittings were never designed to be used with hardlines....
Great deal straight up. You could get close to that price with a dust black build and intelliframe, but no way with the purple anno from Mario, RPG,