Tube adapter made from chromoly steel. With a 5/8" outer diameter. Female style with right-hand 5/16-24 threads. Made with a .058 wall. QA1's weld-in tube adapters are CNC machined to precise tolerances from special easily weldable chromoly steel. Available in a large assortment of sizes to fit most popular tubing, they're an effective way to adapt rod ends to a variety of applications.