These are 5mm Ball Studs from Tamyia.

FEATURES:

Brass colored metal (not steel or aluminum)

INCLUDES:

Ten (10) ball studs

REQUIRES: A 5.5mm wrench to install

SPECS:

Length: 12mm overall 5mm thread length
Diameter: 4.73mm ball 3mm thread diameter

COMMENTS:

These are use in a wide variety of applications.