... 5 year warranty Solar water heater--SKI-TB : Porcelain Enamel Tank to Compacted & Pressurized solar water heaters ... ; Stainless steel sheet, 0.4mm thick;2) Tank material (interior): Titanium Steel, 2mm thick and enamel ... Galvanized Steel, 1.5mm thick;Advantage of porcelain enamel tank:1. Excellent working condition & longer service life: ... solar water heater: porcelain enamel tank, SKI-TB, ISO&CE