... guarantee 15 years vacuum tube guarantee * Water tank of 150L solar water heater, Outer tank material, Color coated steel ... thickness, 50mm Pipe size, 15mm/20mm* Collector of 150L compact solar water heater Tube size58x1800mmOuter tube diameter58mmInner tank diameter47mmGlass ... 51sets/20GP, 100sets/40GP, 125sets/40HQ * Pictures of 150L compact non-pressure solar water heaterWelding for pipes Sketch map ...