1.Beautiful and compact 2.Easy to install and to use 3. ... and has a good insulation effect.c, Water tank: inner tank is stainless steel(0.4 mm 304 food grade ), ... 150L,200L,300L,360L, non-pressurized water tank.f, Heat preservation: 72h~80h, 50mm polyurethane foam inside water tank. ModelGross absorber ... .84581800302802.30142DK5818-364.6581800363502.90162 Vacuum tube stainless steel solar water heater