Doheny’s Heavy-Duty Air Pillow, 4×4 Ft For Round Pools Up To 18 Ft, 1 Pack

Great Quality Heavy-Duty Air Pillows!
Place one of these tough air pillows under your cover to reduce amount of water, snow, ice and leaves that accumulates throughout the winter. The pillow prevents wall damage by equalizing pressure caused by expanding ice. Fill up 2/3 full with air.

For pools up to 18 ft round, you will need a 4×4 ft pillow. For pools up to 33 ft round, you will need a 4×8 ft pillow. For all oval pools, you will need a 4 ft 6 in x 15 ft pillow.