I have used copper-nickel alloy tubing exclusively in auto repairs for the last 15 years for brake lines and transmission cooling lines (for fuel I would recommend nylon repair lines). For me, steel pipes no longer exist. For those of you in the Rust Belt this is a must see. I've seen a replacement steel tube rot after just a year of installation. I've never seen a copper-nickel line fail on me. In addition, this tube bends, takes shape and expands easily, and the connections are almost always tight. Fantastic product!