5/8" UNC HSS Die Nut
Die nuts are suitable for repairing damaged or crossed threads or clearing swarf from threads.
When using a die nut it is not necessary to apply the same level of precise initial alignment required to form a new thread (i.e. with a die) as the nut will follow the existing threads.
They are supplied as hexagon allowing them to be turned by a standard spanner or adjustable wrench without the need for a die stock.