Stainless steel, unpressurized, simply combination,easy operation, more practical for family use, very competitive price Specification:Inner tank: Food grade stainless steel SUS304/2B, 0.41mm thickness. Outer tank: stainless steel SUS304/BA, 0.31mm thicknessFrame:stainless steel, 1.5mm thickness. Insulation: Polyurethane frothing, 50mm thickness. Vacuum tube: Tri-elements(AI-N/SS/CU) coating, Ø ...