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 bowl. 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 anti-sediment 20 micron coiled pre-filtration cartridge set include an economical and durable design, strong and durable spool mesh with no fiber residue, high resistance to elevated temperatures, and ACS certification. Made in Italy, these high-quality wound polypropylene cartridges provide effective pre-filtration of organic impurities, rust, and dust in water. This 20-micron sediment filter coil cartridge is compatible with 9 3/4 and 10 inch filter housings or water purification systems. Ideal for use as pre-filtration before water softeners, upstream of activated carbon filters for drinking water, or in rainwater treatment for irrigation, sanitary systems, or washing machines. For installation, use a standard filter housing or a double transparent filter housing with brass insert, 1 or 3/4 inch, in standard size 9 3/4 or 10 inch. These coiled filter cartridges should be replaced at least once per year. It is recommended to use them for pre-filtration upstream of activated carbon or ultrafiltration cartridges. For optimal water purification, pair with a downstream cartridge of lower micron rating, such as 1 micron, to remove residual organic particles.