PT-011 – Zip-Nut for 5/16″ (8 mm) ACME thread – Quick-release nut for use with BRT-060 and BRT-005 bearing presses. – https://cycling.endurobearings.com/products/pt-011-zip-nut-for-5-16-8-mm-acme-thread-quick-release-nut-for-use-with-brt-060-and-brt-050-bearing-presses