The Hegar urethral sound kit is made for beginner or advenced users. It include 8 rod with two different diameters on each ones and one round end on each sides. Starting at 3 mm up to 18 mm with an increment of 1 mm. Slightly shorter than others on the market, the curved shape will give a completely different sensation. The Hegar urethral sound kit comes with a leather case for easy storage!