Features & Details Enhance Winter Pool Security: This 5-pack of 10 x 0.94 FT double chamber pool cover water bags are designed to add reliable weight secure your pool cover during winter, preventing debris and wind entering. Ideal for in-ground pools, these pool cover water bags are easy to fill, drain, and store, saving you cleanup time in winter. Double-Chamber Anti-Roll Design: The pool cover water tubes features double-chamber construction that boosts internal stability and prevents the bags from rolling or shifting in strong winds. Even during heavy storms, they hold your pool cover firmly in place, making pool maintenance easier. Thickened 0.4mm PVC Material: Made of durable, flexible 0.4 mm PVC, these winter water tube for pool covers water tubes resist UV exposure and minor impacts. Once filled to 50–70% capacity, they provide secure, balanced weight while allowing room for expansion—reducing the risk of bursting from temperature fluctuations. Ideal for year-round use. Heavy-Duty Welded Seams: Each inground pool water tube features high-frequency heat-sealed edges with wide 0.59-inch seams to ensure leak resistance and long-lasting strength. They withstand both summer sun and winter frost without cracking or aging, offering dependable performance season after season. Leak-Proof Twist Caps: Equipped with twist caps and built-in rubber gaskets, these swimming pool cover water bags seal tightly with a simple turn—no leaks, no hassle. The caps also feature anti-drop tethers to prevent loss. Compared to snap-on caps, these pool tubes for covers offer better convenience and a superior seal.