The winter Block 15 Foot Round Above Ground Winter Pool Cover is great for keeping your pool in good condition during the cold, winter months, but it will also make getting your pool back into shape in the spring much easier. This pool cover is made of laminated polyethylene sheeting woven with thick, high-density polyethylene stitching, which ensures superior tensile strength and durability. It has also been treated to provide maximum resistance to damaging ultraviolet rays. For the long life of your pool, choose the Winter Block 15 Foot Round Above Ground Winter Swimming Pool Cover. From the Manufacturer: When the autumn leaves start to change it's time to think about winterizing with Winter Block’s Solid Winter cover. You can rest assured that come next summer you will be satisfied and your pool will be ready for another season of family fun! Solid cover will keep debris and water out of your pool. Lightweight makes cover easy to install. Tightly woven material makes cover very durable for harsh winters. Blue in color comes with perimeter grommets, steel cable and winch. Cover dimensions: 18 feet in diameter, to fit round pools measuring: 15 feet in diameter