Rust prevention is important here in the Midwest Rust Belt where brake lines rust easily. I like AGC tube nuts because they have a rust-resistant brass coating that greatly increases their lifespan. I have relied on AGC tube nuts for braking work for many years. The item I received was in AGC packaging but did not have the typical AGC anti-corrosion brass plating. I checked with the manufacturer if the part number was actually supposed to have a protective coating, so I sent it back for a replacement. The second package had the same problem. I bought the same part number locally for a rust resistant brass finish.