The Nes External Thread Repair Tool is ideal for repairing damaged threads on studs and bolts. No need for a caliper or pitch gauge as tool automatically sizes onto the workpiece, whether SAE or metric, coarse or fine, left handed or right handed. Accommodates 5/32 in. - 3/4 in. (or 4-19 mm). Cutters are HSS induction hardened and will last a few hundred times. When your threads a mess, reach for NES.