UTR KC3 Universal 6-Piece External/Internal Thread Repair UTR External and Internal thread restorers are the ideal tools for saving money during maintenance, plumbing, construction, agriculture, car repair and many other applications where there are components with a damaged thread. Compare the cost of disassembling the part in order to repair a component with the INSTANT repair that need to be performed with the UTR External and Internalthread restorers. From the Manufacturer UTR - The Thread Repair Experts. UTR thread repair tools are a complete line of tools specially designed to repair any defective thread, both internal and external. Our patented tools are universal in diameter and Pitch to give the user a comfortable, easy to use, fast and cost-effective solution for any case of defective thread —in this, we're the experts!