This pack includes standard pre-filtration and anti-sediment wound cartridges, 20 microns in 9 3/4, designed for standard 9 3/4 or 10 filter housing bowls. These anti-impurity cartridges are installed on hot or cold water networks, ideal for filtering solids or fine organic particles. Benefits of the 9 3/4 anti-sediment 20 micron wound pre-filtration cartridge set: Economical and durable, highly valued by our customers. Strong and durable wound mesh ensures no fiber residue in the water. High resistance to elevated temperatures. Made in Italy and ACS certified. High-quality wound polypropylene cartridges provide effective pre-filtration of organic impurities, rust, or dust in water. This 20 micron sediment filter wound cartridge is suitable for 9 3/4 and 10 inch filter holders or water purifiers. These cartridges are perfect for pre-filtration, placed before your water softener, upstream of an activated carbon filtration cartridge for drinking water, or even for treating rainwater intended for irrigation, sanitary facilities, or your washing machine. For installation, you can use a simple filter holder or a double transparent filter holder with a brass insert (1 or 3/4 compatible) in standard size 9 3/4 or 10, available in our store. Additional Information: These wound filter cartridges should be replaced at least once a year. We recommend using these cartridges for filtration or pre-filtration of water upstream of an activated carbon filter cartridge or ultrafiltration cartridge (membrane). It is also advisable to place a cartridge with a lower filtration threshold downstream (e.g., 1 micron) to properly complete the purification of your water and eliminate any remaining traces of organic matter. Available for express delivery in 24 to 48 hours.