This product is a 3/8" UNF HSS die nut, a right‑hand (RH) external threading die supplied in the compact ring style for use with standard die stocks and holders. Its primary use is cutting, repairing and restoring 3/8"‑24 UNF external threads on bolts, studs and turned parts by hand or in light machine applications.

The die is manufactured from M2 high speed steel (HSS) to ISO 4957 material specification and is hardened and tempered to provide the wear resistance and edge retention required for repeated thread cutting. The thread form conforms to the Unified National Fine (UNF) profile, 3/8"‑24 TPI, in accordance with the Unified thread standard (ANSI/ASME B1.1). The die is supplied as a right‑hand cutting tool; it is a solid ring‑type die designed for use in a compatible die stock or holder, with a precision ground cutting face and lead chamfer to start threads cleanly.

Typical applications include automotive thread repair, maintenance of machinery, engineering workshops, plant maintenance and general assembly work where imperial fine threads are required. It is suitable for use on mild and alloy steels, brass, bronze and aluminium; when cutting tougher materials such as stainless steels, reduced cutting speeds and cutting fluid are recommended to preserve tool life.

Key benefits of the M2 HSS 3/8" UNF die nut are its cutting durability and dimensional stability under heat, giving consistent thread form over many uses, and close conformity to the UNF profile for compatibility with mating fasteners. As a carbon alloy HSS tool it is not stainless, so corrosion resistance is limited; occasional oiling and storage in a dry environment will protect the tool. The HSS material delivers greater hardness and wear resistance compared with carbon steel dies, extending service life in production and repair roles.

Duchy Fasteners stocks this 3/8" UNF HSS die nut individually and in multi‑pack options and offers a full complement of imperial dies, die stocks, taps and holders to support workshop and field requirements. If you need alternative sizes or matching taps, please contact our sales team for availability.