... installation 4.Anti-freez,No maintenance Balcony Solar Water Heater, Technical Parameters: Heat Pipe Solar Collector Spec.(mm) ... Vacuum Tube Threei-target tube, copper heat pipe, aluminum fin Manifold Copper flow passage, rockwool/PU insulation, Aluminium alloy ... 2.0mm Material Aluminium alloy plate Accessories Workstation system, Electric heater, E-Parts box, thermostat, Switch, Anode magnesium bar, ...