Aquafilter FCPP5-L ACS-2 series cartridges are made of FDA-approved polypropylene yarn on a polypropylene core that strengthens the cartridge. It has wide chemical compatibility, good heat resistance and low cost. ACS-2 series cartridges are mainly used as the first stage of filtration. The cartridges are characterized by excellent adsorption of sand, silt, rust and suspended solids from drinking water.