Reliable and efficient with twin-glass solar tubes. Easy plug-in installation. Outer tank material: stainless steel plate. Reliable and efficient with twin-glass solar tubes. Easy plug-in installation. Outer tank material: stainless steel 304/2B. Inner tank material: 0.4mm thick SUS304 food grade stainless steel plate. Frame material: stainless steel 304/2B(1.2mm thickness). Superior heat preservation ensured by 50 - 65mm polyurethane foam insulation laye. |