NES 4-piece thread repair set for internal thread use includes 4 internal tools including the Nes 21, Nes 22, Nes 23 and Nes 24. The Nes 21 has a working capacity from 5/16 in. - 7/16 in. The Nes 22 has a working capacity from 1/2 in. - 5/8 in. the Nes 23 from 11/16 in. - 13/16 in. and the Nes 24 from 7/8 in. - 1-1/4 in. Each internal thread repair tool comes with a 60 degree blade made from hardened steel. NES 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 NES External and NES Interal thread restorers.