Just received them today. They utilize the GM swivel base and attach to another make of TPMS valve stem with machine screw. The thread fit is tight so I don't see any issues with it ever loosening.
Found a website off another forum that will modify the stem of GM Trailer TPMS to fit the .625" Hole size.
https://nicholsmanufacturingandweldingservices.com/shop?olsPage=products%2Fcustom-valve-stems-for-tpms