Manufacturer: Timm Medical Technologies Pressure point standard tension ring for erecaid systems large with inside ring dia 7/8", beige, latex-free. The unique upper extruding bumps are positioned to press against the veins that maintain an erection. The lower urethral notch allows for ejaculation. The rings may be used individually or in various combinations to maintain an erection created by the Vacuum Pump. Features: -Rings are latex-free and should be replaced every six months, pending usage. -Rings may be used individually or in various combinations to maintain an erection created by the vacuum pump.