Threadless Disk Top is made of solid 14kt nickel free Yellow or Rose Gold with durable 316LVM ASTM F-138 Implant Grade Steel Pin designed to be practical and easy to use. Fits all sizes of pins and bases in most threadless body jewelry lines. Disk Size: 1.5mm, 2mm, 2.5mm, 3mm and 4mm; Rise: 0.8mm; Pin Gauge: 25g