... Certification:CE,Solar Keymark,ISO9001-2008,SGS,ISO9001-2008 1.Be available in swimming pool, school, hotel, hospital , any other industrial or ... commercial .2. Automatic water supply, good recycling for environmental protection.3.Energy saving, no-pollution, no-harm4.water heater system ... of aluminum alloy4. Hail resistance:25mm5.heat preservation: 72 hours Solar System