For any ball-trap chastity device, there is a gap between the base ring and the cage. A properly sized gap will make sure the cage is secure while still being safe and comfortable.
Most people don't need to worry about exact gap measurements when choosing a device. It's best to start by figuring out what ring size (diameter) feels right on your body. Then, if your testicles still slip through the gap, you can try a ring style that tightens the gap. On the other hand, if your testicles don't have enough room, you can try a ring style that loosens the gap. We suggest leaving precise gap measurements for chastity experts who are on a quest to fine-tune their perfect size and fit.
This page has links to the gap measurements for KINK3D Cobra cages, organized by width. Choose the width you're interested in to see every cage/ring gap measurement. You can also view our base ring size guide for general sizing advice.