A 'penis double ring' typically refers to a type of adult toy or accessory designed to be worn around the penis and testicles. It consists of two rings, often made from stretchy materials like silicone, rubber, or metal, which are designed to be worn simultaneously for enhanced sexual pleasure. The two rings serve different purposes:

1. One ring usually encircles the base of the penis to help maintain an erection by restricting blood flow, potentially leading to harder and longer-lasting erections.
2. The second ring often goes around the base of the penis and the testicles, providing additional support or stimulation during sexual activity.
   
   These rings are designed to increase sensation, enhance stamina, or delay ejaculation, depending on how they are used. It's important to ensure they are worn safely, with consideration for the duration of use and comfort level, to avoid any adverse effects on circulation