I was certified on Wardflex years ago when it first came out (twenty?). Since then my company has used only Gastite. Recently I had a customer with a leak in his old Wardflex. He has a finished basement but the leak was in the mechanical room near where it went into a sofitt. Anyhow I cut the pipe and could not get a new Wardflex fitting on it. I noticed that the fitting was stamped "20M" and the pipe was stamped "20A". Is this incompatable? Can you still get 20A fittings? Thanks.