ACME THREADED INSERTS
http://www.acmeindustrial.com//wp-content/uploads/2019/10/KeylockStud.pdf
Keylocking Studs provide security and repairability in applications where you can’t use a through-bolt/nut combination. They are superior for use in soft materials such as aluminum or magnesium when extra strength, extended thread life and vibration-resistance are required.
