Amazon Has a Helicoil Thread Repair Kit on Sale for Just $13, and It's a 'Lifesaver'

That’s why thread repair kits are essential for any mechanic or DIYer who frequently works with aluminum or softer metals ...
Aerospace Manufacturing and Design

Indexable thread milling grade with PVD aluminum oxide coating

WSM37G-grade inserts are for milling threads with a nominal diameter from 16mm or UNC 3/4 The indexable inserts can be used ...