Hide Your Piercing Blacklight Reactive Tongue Barbell. Ever want to hide your piercing for work but still have a cool barbell you can wear to the club? This is it! This pink acrylic barbell blends with the natural color of your tongue so it is less noticeable under normal conditions; then when the light goes out and the black lights go on your barbell will be a whole different animal. Watch as your barbell goes from hiding your piercing to exploding with uv neon glow. This barbell is a standard 14 GA 5/8" and is perfect for most tongue piercings.