... Frame with stoving varnish All evacuated tubular stainless steel Solar water heater ,SUS304-2B inner tank,advanced argon arc weldding, ... Specifaction of All evacuated tubular stainless steel Solar water heater 1.Inner tank with 0.5mm thicknes food grade ... 360L7.We offer some fittings as optional,such as:Assistant tank,controller,electrical heating element, magnesium anode etc8.Advanced ...