This set of 4.3mm Ti64 Titanium ball studs use the correct vintage 4-40 treads and are made in the USA!  These are a great hop-up for your shelf queen or vintage racer JRXPro or JRXPro SE. 
 
Now available with either a hex our round collar.  If hex collar is selected the 0.1875" stud will be substituted for 0.2" studs.