... anti-freezing,anti-corrosion solar water heater collector: Integrated pressurized solar collectorsPressurized solar collector with SOLAR KEYMARKFeatures:Heat pipe vacuum tube: 58 x 1, ... export cartonQuality certificate: SOLAR KEYMARK, SRCC, ISO 9001: 2000, CE Warranty: 5 years for vacuum tube Evacuated tubeLen(mm)1800mmDia ... 0mmFrameAluminum Alloy,Thickness:2.5mm EN-12975 evacuated tube solar collector