swimming pool solar water heater CCC,ISO,CE,KEYMARK satisfy your requirement swimming pool solar water heaterSpecification:1 .Insulation layer: 35-40mm polyurethane2. Vacuum tubes: 58*1800mm/47*1500mm3. Single side collector:10,15,20,25,30pcs vacuum tubes4. Two-side collector: 50pcs ,60pcses vacuum tubes5. Bracket: 1.5mm galvanized steel plate6. Heat preservation: 72hours7. Hail resistance: ...