Unique shape solar water heater 1.Superior performance 2.Water purifying core, to improve water quality Solar water heater1) Water tank (interior): SUS304-2B food grade stainless steel2) manifold ... vaccum tubes with heat pipe: 14, 16, 18, 20, 24, 30, or 36 units8. Water capacity: 100L, 150L, 200L, 240L, 300L and ...