POOLPURE spa filter cartridge PRB25SF 50-micron trilobal, 50 sq ft media — replaces Unicel C-4405/Filbur FC-2387

The POOLPURE PRB25SF spa filter is a direct-compatible replacement cartridge designed to restore clean, clear spa and small pool water by trapping fine particles with 50-micron trilobal filtration fabric.

When a spa or small pool filter needs replacing, the PRB25SF offers an engineered alternative to several OEM parts (Unicel C-4405, Filbur FC-2387, R172464) with NSF/ANSI 50–tested materials and a durable construction that aims to extend service life and simplify maintenance. It’s built for reliable performance in both residential and light-commercial settings and is trusted by aquatic programs for consistent clarity.

How does the PRB25SF capture fine debris?

The cartridge uses a trilobal fiber weave and a 50-micron filtration layer to catch fine particles that ordinary filters may miss. This combination increases surface area for dirt capture and helps maintain water clarity between cleanings.

• 50 sq. ft. filtration area for high dirt-holding capacity
• Trilobal fabric offers three times the adsorption surface versus standard fibers
• 50-micron media removes hair, sand, dust, and small organic debris

Will this part fit my existing filter housing?

POOLPURE PRB25SF is sized to match common replacements, making it compatible with several part numbers and many spa/pool housings. Verify the dimensions and port openings to ensure a correct fit before purchasing.

• Length: 6 5/8" and outer diameter: 5" for standard housings
• Top and bottom openings: 2 1/8" to match common cartridges
• Cross-references: Unicel C-4405, Filbur FC-2387, Marquis 20342, R172464

How easy is maintenance and cleaning?

The PRB25SF is designed for quick rinsing and repeated reuse; its dirt-locking structure releases trapped debris during backwash or rinse, reducing scrubbing and replacement frequency. Routine care lowers long-term costs and keeps your spa ready for use.

• Patented dirt-locking design lets trapped particles rinse away easily
• Reinforced core and heavy-duty fabric resist wear for longer life
• Simple rinse with garden hose or filter cleaner extends service intervals

What safety and performance standards does it meet?

Materials have been tested for safety and durability, and the product aligns with widely recognized industry expectations for filtration components. POOLPURE participates in industry groups and third-party testing to ensure consistent results.

• IAPMO-tested against NSF/ANSI 50 material-safety standards
• Constructed with reinforced ABS end caps and a strengthened core
• Used in athletic training environments and endorsed by swim programs

Who is this for: The POOLPURE PRB25SF suits homeowners and property managers who need a dependable, cost-effective replacement for worn spa or small pool cartridges. It’s especially helpful for users who want finer particle removal, reduced maintenance time, and longer-lasting components without having to source OEM-labeled parts. If your current cartridge matches the listed dimensions and cross-reference numbers, this replacement is a practical choice to restore filtration performance and keep water clearer between services.