XD Rings: Extend forward by an extra 2.5 mm. This tightens the gap, and also makes the rings more rigid. Good for people with smaller balls to prevent escape.
Rings come in eight sizes, from about 38 mm to about 60 mm diameter
Size 0 is very small. If you're considering Size 0, we recommend trying Size 1 first unless you're really sure.
Sizes 6 and 7 are very large. If you're considering them, we recommend trying Size 5 first unless you're really sure.
