What is G23 Titanium?
G23 solid titanium is by far the top choice for body piercings, and can be safely used for initial piercings. Implant grade titanium G23 (Ti-6Al-4V-ELI, Certified ASTM F136) is the material used in surgical implants, is biocompatible (friendly with your body), much lighter than surgical steel, resistant to body fluids and 100% nickel free.
Q : How do you insert these? Are they 2 piece (like a thread or screw) or is this 1 piece I would have to pop through the holes?
It is 1 piece nose bone type. Nose bone is a straight post ends in a small fixed round ball. This ball is a bit thicker than a stem but small enough to pass through your nose piercing but good enough to keep the nose ring from falling out.