The Compression Brass Sleeves are made available by us are naturally corrosion resistant. They can be used with copper, brass, aluminum or plastic on gasoline, grease, oil, or water. They compress the tubing as you tighten the nut on these fittings, creating a strong seal. They are brass for good corrosion resistance. Use ferrules to create a permanent connection between your air- and water-hose and barbed hose fittings. The offered Compression Brass Sleeves are made for use in the various industries.