Threadless Top Ball comes in 2.5mm, 3mm, 4mm and 5mm ball size and fits into any threadless barbell or base.
Manufactured out of High Polish Implant Grade Titanium (Ti-6AL-4V-ELI ASTM F136).
To secure the inside bar or base, add a slight bend to the pin by simply inserting the pin half way and pushing the top to one side. 
Pin Gauge: 25g