Water Softener Replacement Disk Kit721 8688. The item “Water Softener Replacement Disk Kit721 8688″ is in sale since Sunday, November 28, 2021. This item is in the category “Home & Garden\Home Improvement\Plumbing & Fixtures\Pumps & Water Filtration Systems\Water Filtration Systems”. The seller is “villasboy52″ and is located in Germansville, Pennsylvania. This item can be shipped to United States.