Remembering which filter to use has never been easier! Simply look for the Starburst Number on your filter and match it to the package number.Features KDF® and activatedcarbon. KDF is made of a high purity copper/zinc alloy that creates an electro-chemical oxidation-reduction that neutralizes harmful contaminates including bacteria. When combined with activated carbon it removes or greatly reduces chlorine, heavy metals like mercury, VOC, chemicals, sediment, lime/scale buildup and that hydrogen sulfide that causes a rotten egg smell. Without bacteria present in your water, you€™ll experience greater performance and longevity from your filter and some of the best tasting water you€™ve ever had!Replacement bacteriostatic cartridge for Exterior In-line Water Filter (88-2005) or any standard 10" housing. Up to 11,000-gallon capacity at 2.5 GPM. Addresses bacteria, heavy metals and more. Starburst #5. Priced each.