These round tubes are brass, very strong but light weight. Each size telescopes into the next corresponding size. For use in plumbing, HVAC and automotive. It can be soldered, glued, polished, cut and more→bent to whatever shape required. UPC: 614121181434 Manufacturer Part No: 8143 Brand Name: K & S Diameter: 5/8 in. Length: 12 in. Product Type: Brass Tube Shape: Round Number in Package: 1 pk Application: Scratch builders, modelers, crafts, machine shops and architectural Wall Thickness: 0.014 in. F