Description

Hard pins are technically known as wire thread inserts or helical inserts.
These are precision-formed coils of extremely hard, diamond-shaped stainless-steel wire.
Although they look like springs, they functionas a threaded insert.
Primary Purpose: Their main use is to repair damaged or stripped screw threads. If the threads in a hole (especially in some metals like aluminum) get worn out or stripped, you can drill a slightly larger hole, tap new threads, and then screw one of these inserts in. The insert’s internal threads will then match the original screw size, creating a new, much stronger set of threads than the original.