Stainless steel Solar Water Heater Tank 1.OEM 2.CE,CCC,ISO 3.capacity :500L-1000l Water tank for split solar water heater,for solar energy project,1 ... )outer tank: stainless steel2)inner tank :SUS304-2B food grade stainless steel3)capacity :500L,1000L,1500L,2000L,2500L,3000L,3500L,4000L,5000L4)insulating layer:polyurethane ...