"The Fin Saver" Sacrificial Zinc Anode protects expensive metal parts in Air Conditioners , Heat Pumps and various other applications where galvanic corrosion exists. The "Fin Saver" acts as a sacrificial anode , becoming the weakest metal and therefore corroding before other metals. Provides corrosion protection for HVAC Compresor Lines , Coils and Fins. Specialty zinc alloy for enhanced protection of both aluminum and copper components. Good for Residential , Commercial and Industrial Applications. Can be mounted by the condenser or evaporator coil or both for added protection. Sacrifices itself and begins protecting immediately!