Swimline Super Guard Solid Above Ground Winter Pool Cover 21' Round polaris pool cleaner newer model booster pump pb460 Manufacturer Part # H000055 diameter_8 Manufacturer Part # H000055 Pool Shape Rectangle Plus Extension Flush Right Pool Size 16' x 34' Rectangle + 4' x 8' Flush Right End Step Shipping Info Usually Ships in 7 10 Business Days Warranty 15 Year Manufacturer Warranty Product Features The polyester bonded thread used in LOOP LOC covers costs almost 10 times more than that used by some of our competitors Pool Type Above Ground Pool Size 21' Round Cover Size 25' Round Manufacturer Swimline It helps prevents algae growth