... - Automatically controlled - Highly efficient insulation with polyurethane low pressure olar water heaterMaterial:Inner tank: stainless ... , δ0.31mmBracket: galvanized steel, δ1.5mmInsulation: polyurethane frothing, δ50mmVacuum tube: AL/N coating, 47×1500 ... : 50mmAdvantages:- Automatically controlled- Highly efficient insulation with polyurethane foam- Simple structure, easy to assembly and install- ...