The Purtrex PX20-9-78 is a 20-micron nominal depth filter cartridge. Its graded-density polypropylene construction captures progressively finer particles as water flows from the outer layer toward the core, making it highly effective for reducing sediment, sand, silt, rust, and scale from well water, municipal water, and industrial process water applications.

The Purtrex PX20-9-78 measures 9-7/8 inches in length with an outer diameter of approximately 2-5/8 inches and a 1-1/8 inch inner core diameter. This standard size fits most 10-inch slim-line housings, making it a direct replacement in whole-house filtration systems, pre-filter housings, and reverse osmosis pre-treatment stages.

The Purtrex PX20-9-78 typically lasts 3 to 6 months or up to 15,000 gallons, depending on incoming water quality and daily usage. Because of its true graded-density design, the cartridge offers significantly higher dirt-holding capacity than standard spun or string-wound filters, extending service life. Replace the cartridge when you notice a pressure drop or reduced flow rate.

Yes, the Purtrex PX20-9-78 is manufactured from 100% pure polypropylene with no binders, adhesives, surfactants, or antistatic agents. The materials comply with FDA requirements under Title 21 of the CFR for food and beverage contact, and the cartridge meets NSF/ANSI Standard 42 material requirements, making it safe for potable water filtration.

The Purtrex PX20-9-78 excels in sediment reduction for residential whole-house systems, RO pre-filtration, food and beverage processing, pre-filtration for reverse osmosis systems, and industrial applications such as plating, photo processing, and magnetic media manufacturing. Its thermally bonded polypropylene structure resists unloading and channeling, even under pulsating flow or pressure fluctuations.