The Extendo Nut Driver kit is designed to adapt a standard 1/2" conduit into an extension nut driver for threaded rod. Utilizing the concept of a hollow shank nut driver, The Extendo gives you the flexibility to cut the 1/2" EMT any length you need to drive the nut up the full length of threaded rod. With this tool on hand, you no longer need to buy multiple size hollow shank nut drivers! Save yourself time and money with this complete extension nut driver kit.