I believe these are 16 gauge. They are completely unused. I was going to have my septum pierced, but it didn't work out, so I never got to use these. They were taken out of the original package, but never worn. The metal ones are surgical steel. The black and silver ones came together. I bought the red, silver w/ chain, and silicone ones all singularly. The black/silver set was originally around $11. The red one was around $3. The silver chain one was around $6. The set of clear silicone ones were around $5. Smoke and dog free household, but I do own cats.