REPLACEMENT POOL & SPA FILTERS
Effortless Hot Tub Filter Replacement
Cross-referenced to your exact part number, so you order once and it fits. Subscribe on your own cadence and never think about it again.
Guaranteed fit
Cross-referenced to your exact part number — or it is not a match.
Subscribe & save 10%
Pick a cadence that matches how often you use your spa. Cancel anytime.
No-minimum shipping
Order a single 2-pack or set up a recurring plan — no case minimums.
Common questions
Is this the same as C-4326 or FC-2375?
Yes. This cartridge is a direct cross-reference for Unicel C-4326, Filbur FC-2375/FC-2370, Guardian 413-106, and several other part numbers — same size, same fit.
How do I know this fits my spa?
Measure your current filter: 5 inches in diameter, 13-5/16 inches long, drop-in style with no threaded neck. If that matches, this is a direct replacement.
How does the subscription work?
Pick a Summer or Maintenance cadence at checkout. You get 10% off every shipment, and you can pause or cancel anytime.
Where do you ship?
Enter your address at checkout to see exact shipping options and rates for your location.
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