Works on ALL vacuum systems!. The Tension System is the most important component of the SomaTherapy-ED® system. The Tension System determines the quality of erection achieved when using the SomaTherapy-ED® system. The Tension System is the only component of the SomaTherapy-ED® system that contacts the penis and remains in place throughout sexual intercourse. The result of years of research and development, SureRelease is the world's first disposable tension system. You remove it after use with a quick and easy pull of the tabs. Say goodbye to the discomfort of removing a traditional ring. Since you don't keep SureRelease after use, there's no need to wash it, dry it and store it. SureRelease is all about convenience, comfort and of course, safety. Use the best. Works on all vacuum systems by any manufacturer.