This is a 5/8"-11 UNC hex die nut designed to cut or restore external 5/8‑11 Unified National Coarse (UNC) threads on rods, bolts and studs. Its primary use is for hand or light machine thread cutting and thread chasing where a compact, hexagon-bodied die is required to remove damaged thread material or to re-establish full‑form threads to the ANSI/ASME B1.1 UN/UNF profile.

The die is manufactured from M2 high speed steel (HSS), providing the hardness and hot‑work resistance required for cutting ferrous and non‑ferrous materials. It is supplied with a black oxide finish to reduce surface corrosion and hold cutting oil; the external hex shape allows convenient tightening with a spanner or locating in a die stock. The product is a solid (non‑split) hex die nut producing a standard right‑hand 5/8"-11 UNC external thread with the correct 60° thread form and pitch to match UNC fasteners specified to ANSI/ASME B1.1. It is compatible with common thread gauges used to BS and ISO inspection routines for accepting unified threads.

Typical applications include maintenance and repair in engineering workshops, machinery refurbishment, agricultural equipment servicing, automotive restoration and general plant maintenance where imperial‑threaded parts are present. Because of the HSS cutting material it is suitable for mild and medium carbon steels, cast iron, brass and aluminium; for heavy stainless work a specific stainless‑compatible die or stepped‑cutting procedure is recommended.

Key benefits include the cutting life and thermal stability of M2 HSS, good surface protection from the black oxide finish, and direct compatibility with 5/8"-11 UNC fasteners and fittings. The hex external form provides quick engagement and clearance in tight spaces and is straightforward to use in standard die stocks or with a spanner for manual trimming and repair.

Duchy Fasteners stocks a wide range of imperial and metric dies and die nuts, available individually or in assorted packs and sizes to suit workshop and trade requirements. If you need specific pack quantities or a matched die stock, contact Duchy Fasteners for availability.