Pack of standard pre-filtering and anti-sediment coiled cartridges, 20 microns, 9 3/4 inch, for standard 9 3/4 or 10 inch filter holder bowls. Designed for installation on hot or cold water systems, these anti-impurity cartridges are ideal for filtering solid particles and fine organic matter. Features of the 9 3/4 inch 20 micron anti-sediment coiled pre-filtration cartridge set: economical pack, durable design, and high customer satisfaction. Strong and durable mesh spool ensures no fiber residue in 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, and dust. Suitable for use as pre-filtration before water softeners, upstream of activated carbon filter cartridges for drinking water, or in rainwater treatment for irrigation, sanitary systems, or washing machines. Compatible with standard filter housings, including single or double transparent housings with brass fittings, 1 inch or 3/4 inch, in 9 3/4 or 10 inch sizes. These coiled filter cartridges should be replaced at least once per year. Recommended for pre-filtration ahead of activated carbon or ultrafiltration membranes. For complete purification, it is advisable to use a downstream cartridge with a lower micron rating, such as 1 micron, to remove residual organic particles.