In The Swim Bundle 10-Year 18 Foot Round Pool Winter Cover, Deluxe Pool Winterizing and Closing Chemical Kit, Winter Ball and 4 x 8 Foot Air Pillow has everything you need to get your 18' round above ground pool ready for the cold winter months. The Pro-Strength Polar winter cover is designed with fewer seams, providing increased durability and comes with a 10 year warranty. The Deluxe Closing Chemical Kit includes 1 qt. of Winterizer to help treat and prevent algae, 1 qt. of Winter Stain-Away to prevent metal staining, 2 lbs. of Chlorine-Free Pool Shock to oxidize the water of non-living contaminants, a 2.5 lbs. Winter Pool Floater to help maintain water clarity and a Winter Sorb to absorb oils and scum in the water. Also included is a WinterPill Winterizer which slowly releases a special blend of enzymes, clarifier and scale inhibitor further increasing protection of the pool water throughout the winter. A 4' x 8' Air Pillow is also included to reduce strain on the winter cover and pressure of ice freezing, helping to protect above ground pool walls.