Ecosavr 99999 Solar Fish Liquid Pool Cover for Swimming Pools Cuts overnight heat loss in half - get your pool warmer, quicker. And keep it that way Conserves water lost to evaporation by up to 50% - less cold water you need to refill your pool with Easier to use than plastic pool blankets - no more rollers, backaches or frustration It won't break apart, leaving pieces to clog your filter Can be used on uniquely shaped pools and those with water features, like spillovers or waterfalls