Material: stainless steel/titanium Sold by pair. Existing size has below options. 1.2mm bar gauge,8mm ball, inside size 10mm*15mm 1.6mm bar gauge,8mm ball, inside size 10mm*15mm 2.0mm bar gauge,8mm ball, inside size 10mm*15mm 2.5mm bar gauge,8mm ball, inside size 10mm*15mm 3.0mm bar gauge,8mm ball, inside size 10mm*15mm 1.2mm-2.0mm bar is Externally Threaded. 2.5mm and bigger than 2.5mm bar is internally threaded. If you need any different size of above options, contact me for customize size(bar gauge,ball size,U shape inside size) to place your order. Features of titanium: In same volume, titanium is about 60% of the weight of stainless steel Non-magnetic and non-toxic Excellent corrosion resistance, will not rust ever Outstanding biocompatibility, will not cause allergic reactions Recognized as the best body piercing material The safe anodized coloring process principle gives the product more color choices, not only practical and more beautiful like your piercing jewelry or chastity jewelry