Millionsun has a solar storage tank workshop to produce pressurized and unpressurized tank according to different demand. Corrosion and hard water is a challenge to tank, especially pressurized tank, we already have good solution. Stable product had exported to Europe and Africa. Besides good price performance ratio is also advantage for us. Features: Attractive coating appearance Inner tank with stainless steel SUS316 or SUS304 Temperature and pressure relief valve Protect Electric booster inside as alternative heating element Easy matching to residential solar systems Automatic temperature control Directly foamed up polyurethane insulation to reserve heat