The 3 Piece Nut is part of the Buyers Products line of JIC 37-degree flare tube fittings. The fittings feature tough carbon steel construction, 3 piece flare sealing for a tight, secure connection, and a corrosion-resistant zinc finish. Fitting conforms to JIC and SAE specifications. Buyers Products tube fittings are used with copper, brass, steel, aluminum, and other tubing that can be flared. They are rated at up to 10,000 PSI depending on tube size.