Features: 1) Superior heat preservation ensured by 75mm polyurethane foam insulation layer 2) Designing the immersion heater hole in advance for the cloudy, snowy, and rainy days 3) Suitable for mains pressure water (up to 0.6MPa) 4) Immersion heater connects with SFH water tank 5) Material: galvanized sheet 6) Inner tank material: using pressurized material, the inner tank has the advantages as follows: a) No corrosion: can prevent corrosion lead from chlorine ion, sea water, salt water or buck water b) No leakage: applied for special anti-corrosion layer c) Sanitary water: the qualities showed above make it possible that water quality is pure and no twice pollution 7) Able to be used in all climates 8) Automatic water supply, could supply water self-acting without any other installation and could able to be pressured