The Heat Pipes series solar Collector are always connected with existing heating supply device, the selective coating on the inner cover or the evacuated tubes converts solar energy into heat energy and transfers heat to the heat pipes by aluminum Fins, The liquid in the heat pipe changes into vapour which rises to the condenser. the heat conducts to the heat transfer liquid vis a copper pipe. this transference of heat into the liquid creates aa continuous circulation as long as the collector is heated by sun the KEG58 solar collector manifold is made of 100% aluminum, the thickness of the copper pipe in the manifold is 1.0mm ,15years product guarantee