solar water heater NS-58-24 Manifold Casing Material Aluminum Alloy/304 Stainless steel Frame Material 1.2mm 304 Stainless Steel Header Pipe Material 99.93 pure Copper lead free 45 silver brazing Insulation Compressed Glass Wool - K = 0.043W/mK Rubber Seals and Rings silicone rubber installation angle 40