Spiral Twister HELIX Ring, Amethyst purple crystal inset stone, 16 gauge, eyebrow barbell piercing, hoop titanium Unusual & striking "Twister Ring" with sliding inset Amethyst purple colored crystal 16 gauge wire, 8mm wide, about 2mm inset "STONE" Stone slides out to insert wire, then slide back in and "click" to hold in place Popular in brow, barbell, and similar cartilage piercings