Our classic glass skull tops have been updated and downsized so they fit in more piercings. The threadless titanium jewelry is very eye-catching and certain to be a favorite. To use threadless jewelry, simply put a slight bend in the durable 25 gauge pin before inserting into the base. Compatible with all sizes of threadless bases. Manufactured out of High Polish Implant Grade Titanium (Ti-6AL-4V-ELI ASTM F136).