Airgas on Dort Hwy is a great store with many options for metal working to choose from. Where they have fallen short is the billing department. I continue to receive bills with past due charges on it for a lease tank that I had returned (even had the invoice showing the tank had been returned and lease should have ended). I am at a loss to what to do next. I have called, written and visited the store, showed them the invoice confirming with Airgas service rep's, at the Dort Hwy, Flint, MI location counter, I do not owe this bill and today in the mail another bill from their headquarters in Chicago, ILL.