Is it time to winterize your pool? Then this plug cap will be the perfect addition to that closing of your pool. The threaded plug is slotted for easy installation and removal. Features: For use with threaded wall returns and skimmers. Features a heavy duty o-ring for tight sealing. Easy to use - simply screw a threaded plug into each return line and drainage inlet after the lines have been blown out. Perfect for preventing costly damage to your plumbing lines throughout the winter. Dimensions: 1.5" diameter. Material(s): plastic/rubber