Wound polypropylene thread filtering from 10 to 50 micron (throw-away cartridge). For filtration of: sand, scale, lime, rust, fine particles. Domestic use: filtration of drinking water, protection of taps, boilers, washing machines and other installations for potable water. Technical use: pre-filtration for water-pumps, irrigations systems, protection of industrial installations; filtration of water and other liquids in industrial applications: chemical, petrochemical, photographical, electroplating, pharmaceutical. Average life-span: from 3 to 6 months. Maintenance: none.