... .1% spare vacuum tubes and spare parts for free Integrated Pressurized Solar Water HeaterSpecification:inner tank: food grade sus304-2B stainless steel, 1 ... heater (1.5kw, 2kw, 2.5kw, 3kw), assistant tank( 5L, 8L, 12L, 15L), magnesium barFeature:Working with high pressure, so do the water ... work in the event of occasional tube breakage. Parameter Compact Pressurized Solar Water Heater