Solar System Expansion Vessel, Max. working pressure 8-10 bar, Working Temprature: -10 C to +110 C, Peak Temprature (max. 2 hours): +130C, Precharge Pressure: 3 bar, Available Capacity (8 lit through 300 lit). Materials: Sturdy Structure in high-quality Steel, Upper Shell (Water Side) come with TOP-PRO (internal protection makes these vessels suitable foe use with corrosive water such as heated water, Painting with long life epoxy powders white colour, Bladders in special rubber in special SBR rubber