Balcony solar water heater, 1.OEM offered 2.Pressurized, best efficiency 3.Simple installation 4.Anti-freez,No maintenance Balcony Solar Water Heater, Technical Parameters: Heat Pipe Solar Collector Spec.(mm) Φ47×850 Φ58×850 Tube (pcs) 12 / 15 / 18 / 20 / 25 / 30 Vacuum Tube Threei-target tube, copper heat pipe, aluminum fin Manifold Copper flow passage, rockwool/PU insulation, Aluminium alloy ...