NewView™ refrigerator water filters contain a compressed carbon bloc which provides tremendous capacity to remove and reduce impurities and sediment that may be in your drinking water. Unlike most replacement filters which can lose up to 50% filtration efficiencies due to clogging, NewView™ Filters use a specialized NSF51/61 Certified Activated Carbon that is precisely mixed with the world's most advanced resin and compressed using sinterizing technology. This sophisticated process increases filtration effectiveness allowing more harmful contaminants to be removed from the water giving you the CrystalPure™ Advantage!