Micron Pre-Filter Cartridges for Standard RO Systems. Features: 1-Micron dual density gradient sediment filter is highly recommended due to longer life and cost effectiveness. Precision manufactured from 100% pure Polypropylene fibers. The fibers have been carefully spun together to form a true gradient density from outside to inside surfaces. 9-7/8" standard size cartridge is self-sealing for a tight fit in RO units.
