Robelle 3510 Swimming Pool Triple-Action Winter Kit, 10000-Gallon Includes the chemicals you need to close your pool, protect your pool this winter, and yield the most stress-free spring opening youve ever had The Summer and Winter Multi-Purpose Algaecide will prevent algae growth during the winter months The Winter Stain & Scale Control will prevent stain and scale while the pool is closed Oxidizing Shock and Swim is the highest strength non-chlorine oxidizing pool shock - effective at eliminating organic contaminants