Push-fit range for use with stainless steel. Superseal is a special fitting designed to provide extra grip on hard steel, stainless steel and other polished metal tubing. The Superseal design features a collet with integrally molded stainless steel teeth similar to the standard Super Speedfit design, but incorporating an additional hand-operated nut and wedge shaped plastic washer to apply extra pressure to the collet and the double 'O' ring seals. This ensures that the collet teeth bite thoroughly into the tube to provide grip while, at the same time, compressing the 'O' rings to further enhance sealing. Like other John Guest fittings, Superseal is suitable for potable liquids and other food quality applications.