These ring can help you stay harder longer and prolong ejaculation. Cloud 9 cock rings are made of phthalate-free, non-toxic thermoplastic rubber (TPR). The smallest ring is for maximum erections; the medium ring is for harder erections; the large ring can encircle the upper part of your scrotum to help prevent premature ejaculation. The rings are comfortable and made specifically for your safety and hygiene during your intimate play. Cloud 9 cock rings can be used individually or together. Cock rings give you a longer lasting erection by trapping the blood supply in the penis and intensifying your orgasm! Cock rings are ideal for men suffering from erectile dysfunction and premature ejaculation. Always use a water-based personal lubricant with this product for maximum pleasure. Do not wear a cock ring for more than 30 minutes at a time.