... -10 per hole 3. 15Years Warranty for vacuum tu Non-pressure solar water heaters(ss)1.CE,ISO9001,CCC, 2. Anti-freezen ... Warranty for vacuum tu Control the use of special effects, water temperature and faster heating. Advanced exh-aust work Arts, the heat ... , Dual-level ramp.Technological advance: the use of more safe, non-troubled waters, anti-burst, antifreeze, E-nrichment process.Collector device ...