This Zinc Anode Weight is designed to stop metal erosion, and plaster discoloration due to electrolysis.
Keeps skimmer basket in place.
The way that a zinc sacrificial anode works to protect metal in your pool is by a process called cathodic protection. The zinc has a more active voltage than the other metal and therefore will break down before any damage is done to the surrounding metal, protecting it. The offending forces of oxidation and reduction take place on the sacrificial anode instead of metal in your pool.