Nut Thread: 3/4"(19mm) G Thread. Tube with Compression Nuts that can fit most brand compressors. Note: 1.The mainline that carries compressed air from the pump head to the air tank, the discharge (or “transfer”) tube is typically made of copper, aluminum, or stainless steel braided material. 2.Be sure all compression fittings and threads have tight seals and don't leak, and replace if kinked or cracked. Package Contents: 1pcs Air compressor aluminum tube.