... 4. Buyer label offered Supply Kinds of Solar Boilers(Solar Water Tanks) - Factory Details: Capacity: 80L,100L,150L,200L,250L,300L,400L ... layer: High density polyurethane foamCoils in tank as heat exchanger: copper coils or stainless steel coilsQuantity of coils: Can be single ... back up Inner tank Supply Kinds of Solar Boilers(Solar Water Tanks) - Factory