The Watts FPMB5-20 is a 5-micron pleated sediment filter cartridge. This rating means it effectively captures sediment, dirt, sand, rust, silt, and scale particles down to 5 microns in size, making it ideal for whole house and point-of-entry applications where clean, sediment-free water is essential. The pleated design provides a larger surface area compared to standard spun or melt-blown filters, allowing for higher dirt-holding capacity and longer service life.

The Watts FPMB5-20 measures 20 inches in length with an outer diameter of 4.5 inches (commonly known as a "Big Blue" size). It is designed to fit standard 20" x 4.5" Big Blue-style filter housings, including Watts, Pentek, and other compatible whole house systems. Its large capacity makes it suitable for high-flow residential and light commercial applications, delivering flow rates up to 20 GPM depending on the housing used.

The Watts FPMB5-20 typically provides a service life of approximately 3 to 6 months, depending on your incoming water quality, sediment load, and daily usage. For households with heavy sediment or well water, the filter may need replacement closer to the 3-month mark, while homes with cleaner municipal water may extend usage up to 6 months. We recommend replacing the cartridge immediately if you notice a significant drop in water pressure or visible discoloration.

The Watts FPMB5-20 is manufactured from FDA-compliant polypropylene materials, ensuring it is safe for potable water use. The pleated polypropylene media is tested to NSF/ANSI Standard 42 guidelines for material safety and mechanical sediment reduction. Because it is constructed without adhesives, surfactants, or binders, the FPMB5-20 will not impart taste, odor, or chemicals into your filtered water supply.

The Watts FPMB5-20 is specifically engineered to reduce sediment, sand, silt, rust flakes, scale particles, and other suspended solids 5 microns and larger. Unlike traditional spun or melt-blown sediment filters, its pleated polypropylene design offers up to 3x more surface area, resulting in higher dirt-holding capacity, lower pressure drop, and longer filter life. It is also reusable in some light-duty applications — the pleats can be gently rinsed to extend service life before replacement becomes necessary.