The internal threaded stud pot magnet is also known as a female threaded stud pot magnet. They consist of a ferromagnetic mild steel cup containing a magnet (usually a disc magnet) with a ferromagnetic mild steel stud / boss / bush mounting at the back of the pot magnet into which a threaded hole has been made.
These pot magnets are known as female threaded stud pot magnets because the internal threaded hole could take pot magnets with threaded bar at the back (external threaded stud pot magnets / male threaded stud pot magnets) as well as bolts. Because the mild steel is stud / boss is threaded there is decent thread length allowing reasonably high torque to be applied to securely hold each pot magnet in place. The ferrite version of the internal threaded stud pot magnet can be used at temperatures up to +120 degrees C and is suitable for almost any application.