UNF

UNF 7/8 "US Hand Tap Set - DIN 2181 Material: HSS - High Speed ??Steel UNF - Unified thread fine (this is the unification of the American and British whitworth threads)

UNF 9/16 "American hand tap set - DIN 2181 HSS - High Speed ??Steel UNF - Unified thread fine (this is the unification of the American and British whitworth threads)

Left American hand tap UNF 3/8 - set Size: UNF 3/8(equivalent to 9,525mm) Pitch: 24 feet per inch, fine left Fitting: 2B Standard: DIN 2181 Material: HSS - High speed steel UNF - Unified fine thread(it is a unification of American and British  © ho whitworth thread)