KXMATRIKX +5 filter :Carbon Block Filter is composed of coconut shell carbon and provides down to 2 micron nominal filtration and 5 micron absolute filtration. The Matrikx +5 Filter is uniquely constructed to better absorb chemicals such as VOC's and chlorine taste & odor. The KX +5 series are NSF/ANSI Tested and Certified for Material Requirements only. This filter was performance tested & verified by Independent Laboratory Testing. The 10" Big Blue Matrix +5 Carbon Block Filter Reduces. MATRIKX  +5 water filters are made to fit most standard household, commercial, and industrial housing.