Franklin 20" x 4.5" OD Dual Gradient Spun Poly Filter Cartridge, NSF 42 Certified (FWPS-DG Series)

Product Overview The Franklin 20" x 4.5" OD FWPS-DG Series Dual Gradient Spun Poly Filter Cartridge delivers high-efficiency sediment filtration for demanding commercial, industrial, and high-flow residential applications. Constructed from 100% polypropylene fibers using thermal bonding technology, this cartridge offers exceptional contaminant retention without the use of adhesives, surfactants, or binders. Its advanced dual-gradient density design traps larger particles at the outer layer while finer inner fibers capture smaller sediment deeper within the cartridge. This structure increases dirt-holding capacity, reduces pressure drop, and extends operational life in systems with high sediment loads. The extended 20" Big Blue configuration provides greater filtration capacity and longer replacement intervals, making it ideal for applications where minimizing maintenance and downtime is critical. Key Features Extended 20" cartridge for increased contaminant capacity Large 4.5" OD Big Blue design supports higher flow rates Dual-gradient density structure improves filtration performance High dirt-holding capacity for longer service life 100% polypropylene construction for broad chemical compatibility Thermal-bonded manufacturing without adhesives Resistant to bacterial attack and chemical degradation NSF 42 and FDA CFR Title 21 certified Recommended Applications Commercial water treatment systems Whole-house water filtration Reverse osmosis pre-filtration Food & beverage processing Process water filtration Chemical processing systems Electroplating operations Specifications Specification Detail Series FWPS-DG Series Cartridge Length 20" Outside Diameter 4.5" Media 100% Melt-Blown Polypropylene Construction Dual Gradient Thermal Bonded Max Operating Temperature 60°C (140°F) Nominal Replacement Pressure Drop 1.5 Bar (22 PSI) Maximum Pressure Drop @ 20°C 3.2 Bar (46.4 PSI) Maximum Flow Rate 20 GPM Micron Ratings Available 25/1, 50/5, 75/25 Micron Certifications NSF 42, FDA CFR Title 21 Frequently Asked Questions Why choose a 20" filter cartridge? A 20" cartridge provides increased dirt-holding capacity and longer filtration cycles compared to standard 10" filters, reducing maintenance frequency. What are dual-gradient micron ratings? Dual-gradient ratings such as 50/5 micron indicate that the outer layer captures larger particles while the inner layer filters finer sediment for improved overall efficiency. Is polypropylene chemically resistant? Yes. Polypropylene is highly resistant to many chemicals and process fluids, making it suitable for industrial and commercial filtration applications. Can this filter be used before reverse osmosis systems? Yes. FWPS-DG cartridges are commonly used as pre-filtration stages to protect RO membranes from sediment contamination. Will the filter media support bacterial growth? No. Polypropylene media is resistant to bacterial attack and designed for reliable long-term filtration performance.