The C-RING erection rings set is made of very elastic silicone. The rings fit every penis and, by applying pressure, effectively extend the duration of intercourse. Their irregular shapes pleasantly stimulate the vagina and clitoris. Each ring has a different size - placed during erection at the base of the penis, it will ensure maximum erection until the end. The product is made of soft silicone, safe for the skin, hygienic, and durable at the same time. This material is extremely elastic, so it fits every penis.