SpectraPure Carbon Block Filter Catridge 0.5 Micron, 10-Inch Sediment removal at its finest Scientifically-advanced sediment filters are designed specifically for use in RO and RO/DI units in areas where high sediment is a problem Enhanced design features graduated sediment removal to trap larger particles near its surface and minute particles in the center Designed for a longer life cycle and greater particulate holding capacity Truly purify your aquarium water supply with this filter cartridge