Our Titanium is Nickel Free, half the weight of Steel, without the use of dyes to color it. We only use G23TI Surgical Titanium. This is the grade that is used worldwide for heart valves, pacemakers, and implants. It should be noted that G23TI Titanium costs more then double the price of the cheaper commercial grades (CP Titanium 1,2, 3, 4, or 5), that are usually offered to you in body jewelry by other company's. Circular Barbells are designed for clients who frequently remove or change their jewelry. Circular barbells can be worn with virtually any piercing. These smaller gauges are externally threaded for a precision fit. Circular Barbell's are measured using the inside diameter.