A tube formed of a hot-rolled aluminum sheet product , the tube having an internal surface within the tube and an external surface outside the tube , wherein the tube comprises: - a core layer consisting of a 6xxx aluminum alloy, the 6xxx aluminum alloy comprising: - 0.2-2.0% Si; - up to 1.0% Fe; - 0.10- 1.0% Cu; - up to 1.0% Mn; - 0.25-1.5% Mg; - up to 0.25% Cr; - up to 0.25% Zn; - up to 0.2% Ti; and - up to 0.2% Zr, the balance being aluminum and impurities; and - an outer liner layer disposed on a first side of the core layer , the outer liner layer consisting of one of: - a 3xxx aluminum alloy having an additive of 1-3% Zn; and - a 7xxx aluminum alloy having 0.5-5.0% Zn, wherein the aluminum sheet product is in the form of the tube with a multi-layered structure, the tube having a round cross-sectional shape with the outer liner layer defining the external surface of the tube , wherein the internal surface of the tube is on a second side of the core layer , the second side being arranged opposite to the first side, wherein a welded joint is configured to bond a first edge and an opposed second edge of the aluminum sheet product together to form the tube , the welded joint extending along a length of the tube , wherein the tube has a thickness in the range of 0.3 millimeters to 1.5 millimeters, the outer liner layer having a thickness between 5% and 20% of the total thickness of the tube , wherein tube has an O temper pre-braze tensile strength of at least 97 N/mm 2 (14 ksi), and wherein the post braze corrosion potential difference between the outer liner layer and core layer is at least 30 millivolts. - a core layer consisting of a 6xxx aluminum alloy, the 6xxx aluminum alloy comprising: - 0.2-2.0% Si; - up to 1.0% Fe; - 0.10- 1.0% Cu; - up to 1.0% Mn; - 0.25-1.5% Mg; - up to 0.25% Cr; - up to 0.25% Zn; - up to 0.2% Ti; and - up to 0.2% Zr, the balance being aluminum and impurities; and - 0.2-2.0% Si; - up to 1.0% Fe; - 0.10- 1.0% Cu; - up to 1.0% Mn; - 0.25-1.5% Mg; - up to 0.25% Cr; - up to 0.25% Zn; - up to 0.2% Ti; and - up to 0.2% Zr, the balance being aluminum and impurities; and - an outer liner layer disposed on a first side of the core layer , the outer liner layer consisting of one of: - a 3xxx aluminum alloy having an additive of 1-3% Zn; and - a 7xxx aluminum alloy having 0.5-5.0% Zn, - a 3xxx aluminum alloy having an additive of 1-3% Zn; and - a 7xxx aluminum alloy having 0.5-5.0% Zn, wherein the aluminum sheet product is in the form of the tube with a multi-layered structure, the tube having a round cross-sectional shape with the outer liner layer defining the external surface of the tube , wherein the internal surface of the tube is on a second side of the core layer , the second side being arranged opposite to the first side, wherein a welded joint is configured to bond a first edge and an opposed second edge of the aluminum sheet product together to form the tube , the welded joint extending along a length of the tube , wherein the tube has a thickness in the range of 0.3 millimeters to 1.5 millimeters, the outer liner layer having a thickness between 5% and 20% of the total thickness of the tube , wherein tube has an O temper pre-braze tensile strength of at least 97 N/mm 2 (14 ksi), and wherein the post braze corrosion potential difference between the outer liner layer and core layer is at least 30 millivolts. <EOS>