This Turnlock part HSTHGF5056S is a flat grommet to install the stud in the panel and holds the stud in place. Important is that since this grommet will swage 90 degrees, you'll need a protection ring to protect the panel:
turnlock HSTHS08S
Material
Stainless steel
Type
Grommet Flat
Headstyle
Flat Grommet
Turnlock can offer you the HSTHGF5056S with Certificate of Quality, Certificate of Conformity and Certificate of Origin on request. Turnlock is offering HSTHGF5056S as factory new.