The Female Leather String comes with an angled stainless steel hook that has a 3 inch long, 1.25 inch (maximum diameter) stainless steel butt plug attached. Work the hook into the best angle and insert the metal anal plug. The metal buckle fastening leather straps are also fully adjustable to achieve the best fit. The metal plug can also be detached for use on its own as a butt plug or as a vaginal plug. One size fits the majority.