This Robelle Mesh rectangular mesh winter pool cover features a 10 x 10 Scrim count (threads per square inch) and a material weight density of 3.1 ounces per square yard. The Gray/Black mesh material has been treated to inhibit damaging ultraviolet rays. Made of polyethylene, this exceptional quality in-ground winter pool cover has a 4-ft overlap, allowing the cover to be secured with water tubes on the pool deck. There are grommets approximately every 4 feet. Water bags should be used to secure the cover onto the deck. Water Bags are sold separately. The overall size of this cover is 34'W x 54'L. It is designed for rectangular in-ground pool. All Robelle Mesh winter pool covers come with a 10-year warranty.