Silicone Gaskets for JIS1.5S hull are heat resistant silicone seals for general connections. Material: Silicone (for food plumbing) 1.0S - 1.5S has the same outer diameter. Because the inner diameter is different, please use a gasket that matches the size of the pipe. We recommend checking in the drawing. Please note that if not in size, it may cause contamination or bacterial colony.