Laguna Rubber Door for PowerFlo 5000 Skimmer Filter Reversible argyle raincoat Used for overwintering purposes, the door provides a tight and secure fit to prevent unwanted material from entering the skimmer filter Made of flexible yet durable rubber material It is designed to withstand the cold winter months Measures 15-3/5-inch length by 9-1/2-inch width by 4/5-inch height