Listing we opened and checked. Match the diameter, length and both fittings on this page before you order. The price is on Amazon; we do not print one.
PDC Spas OEM FLT-201TL spa filter (C-4326)
Luxury, Premium, SE and LX
Replacement numbers
Unicel C-4326, Pleatco PRB25-IN
Fits PDC Spas OEM FLT-201TL.
Diameter 4-15/16" (125 mm)Length 13-5/16" (338 mm)25 sq ft1 model listedUnicel C-4326
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| Unicel | C-4326 |
|---|---|
| Pleatco | PRB25-IN (Unicel cross-reference PDF p.47: C-4326 = PRB25-IN. Spec table PDF p.32: 5" × 13-5/16", 2-1/8" open, 3 oz, 25 sq ft. Deactivated PDC25-AFS points at PRB25-IN; PDC’s 2025 guide does not print PDC25-AFS.) |
| Filbur | FC-2375 |
| Top | 2-1/8" (54 mm) / open |
| Bottom | 2-1/8" (54 mm) / open |
Bottom: 2-1/8" (54 mm) / open
Drawn to scale from the listed diameter and length and open-end sizes. Handles, threads and closed ends are drawn as symbols, not to scale. 25 sq ft media.
For PDC Spas, C-4326 cartridge (OEM FLT-201TL) sits in Luxury, Premium, SE and LX. The cross-reference prints OEM FLT-201TL; Unicel C-4326; Pleatco PRB25-IN; Filbur FC-2375. 4-15/16" across, 13-5/16" long, top 2-1/8" / open, bottom 2-1/8" / open, 25 sq ft.
Catalog note for FLT-201TL: PDC’s 2025 guide: Luxury, Premium, SE and LX, 1990 to present, FLT-201TL, 25 sq ft, 5" × 13-5/16", 2-1/8" holes, named as Unicel C-4326. Unicel’s spec table prints C-4326 at 4-15/16" × 13-5/16", 106 pleats, 3 oz, 25 sq ft. Pleatco prints PRB25-IN at 5" × 13-5/16". Filbur’s size table crosses FC-2375 to C-4326. Filbur’s PDC section prints FC-2370 as C-4325, which is a different, 11-7/8" cartridge.
C-4326 (OEM FLT-201TL), Pleatco side: Unicel cross-reference PDF p.47: C-4326 = PRB25-IN. Spec table PDF p.32: 5" × 13-5/16", 2-1/8" open, 3 oz, 25 sq ft. Deactivated PDC25-AFS points at PRB25-IN; PDC’s 2025 guide does not print PDC25-AFS..
FLT-201TL, Filbur note: Dimensional listing PDF p.9 (printed p.17): FC-2375 = PRB25-IN = C-4326, 4-15/16" × 13-5/16", 25 sq ft. Same page: FC-2370 = PRB25-IN-4 = C-4625. PDC Spas section PDF p.23 (printed p.45) prints FC-2370 as C-4325, not C-4326..
Model list attached to C-4326 cartridge (OEM FLT-201TL): Luxury, Premium, SE and LX, years 1990 to present, listed by PDC Spas Common Replacement Filter Elements (2025) (FLT-201TL, 25 sq ft open cartridge. PDC does not split these four series onto different parts.).
C-4326 is easy to confuse on the PDC Spas table. 4CH-949 differs by Unicel 4CH-949, Pleatco PWW50L, Filbur FC-0172, 13-1/2" long, top v-groove semi-circular handle, bottom 2" female SAE thread, 50 sq ft, OEM FLT-SWIM50-CART, note says Dimensions shown are Unicel’s: 4-15/16" × 13-1/2", v-groove handle, 210 pleats, 3 oz, 50 sq ft, 2" female SAE, note “For use on 1-1/2" male SAE stand pipe.” PDC’s 2025 guide rates FLT-SWIM50-CART at 50 sq ft, 5" × 13-1/16", 1-1/2" female SAE (38 mm), for Synergy, Summit, Splash, Vitality, and the hot-tub zone of dual-zone models, 2009 to present, and names Unicel 4CH-949. Pleatco prints PWW50L at 5" × 13-3/16", 1-1/2" female SAE, 50 sq ft, OEM 817-4050. Unicel’s Waterway line also prints 817-4050 as 4CH-949. PDC does not print 817-4050. Filbur’s size table prints FC-0172 at Unicel’s 13-1/2" and 2" female SAE.. C-4405 differs by Unicel C-4405, Pleatco PRB25SF-JH-PAIR, Filbur FC-2387, 6-5/8" long, OEM FLT-171-CART, note says Shown at 25 sq ft because that is what PDC’s 2025 guide prints for the element (LifeStyle, XD2 spa side, and River, 2010 to present), 5" × 6-5/8", 2-1/8" holes, named as Unicel C-4405. Unicel’s OEM cross-reference prints 50 in the square-foot column for C-4405, and the spec note says two cartridges per set. The spec row itself does not print a square-foot figure. Pleatco prints PRB25SF at 25 sq ft for one cartridge and PRB25SF-JH-PAIR at 50 sq ft, and its cross sends C-4405 to the pair. Filbur prints FC-2387 at 50 sq ft, “6 sets,” with the same two-per-set note..
Left blank on purpose: Diameter 5" (PDC, Pleatco) vs 4-15/16" (Unicel, Filbur). Filbur’s PDC section prints C-4325 on the FC-2370 row; its size table prints FC-2370 as C-4625 and FC-2375 as C-4326..
Source locations for this PDC Spas row: PDC Spas (manufacturer filter guide, 2025) on C-4326 (Luxury, Premium, SE and LX, 1990–present: FLT-201TL, 25 sq ft, 5" × 13-5/16", 2-1/8" holes, Unicel C-4326). Unicel 2026 Replacement Guide on C-4326 (PDC Spas block, PDF p.47 (printed p.43): C-4326, 4-15/16" × 13-5/16", 25 sq ft, 3 oz. Spec table PDF p.9 (printed p.5): 106 pleats, 2-1/8" open ends. C-4625 is the 4 oz cartridge of the same size.). Pleatco 2023 Catalog on C-4326 (Spec table PDF p.32: PRB25-IN, 5" × 13-5/16", 3 oz, 25 sq ft. Cross-reference PDF p.47: C-4326 = PRB25-IN.). Filbur Catalog & Reference Guide on C-4326 (Size table PDF p.9 (printed p.17): FC-2375 = C-4326. PDC section printed p.45: FC-2370 printed as C-4325.).
Hot tubs listed for this cartridge
The rest of the PDC Spas model list is the PDC Spas filter by model and year lookup.
| Model / system | Years | Listed by |
|---|---|---|
| Luxury, Premium, SE and LX (FLT-201TL, 25 sq ft open cartridge. PDC does not split these four series onto different parts.) | 1990 to present | PDC Spas Common Replacement Filter Elements (2025) |
Check the cartridge you removed
Measure diameter, length, and both ends, then compare them with the figures above. The steps are in the measuring guide. Why the bottom decides whether it seals: open-end vs threaded filters. Power, the retainer, and not running the spa empty: how to install a cartridge. Number formats: how Filbur, Unicel and Pleatco numbers compare.
The same C-4326 number is also on the Hot Spring, Hot Spot, Jacuzzi, Beachcomber, Coleman Spas pages.
Other PDC Spas cartridges
- 4CH-949 cartridge (OEM FLT-SWIM50-CART), 4-15/16" (125 mm) × 13-1/2" (343 mm)
- C-4405 cartridge (OEM FLT-171-CART), 4-15/16" (125 mm) × 6-5/8" (168 mm)
- C-4975 cartridge (OEM FLT-SWIM75-CART), 4-15/16" (125 mm) × 20-1/8" (511 mm)
- PRB7B cartridge (OEM FLT-118), 5" (127 mm) × 4-5/8" (117 mm)
- 4CH-15 cartridge (OEM FLT-1000-CART), 4-5/8" (117 mm) × 5-3/16" (132 mm)
- C-4310 cartridge (OEM FLT-101SK), 4-1/4" (108 mm) × 4" (102 mm)
Every number on this row, on one screen: cross-reference lookup. Published clean and replace intervals for this cartridge, and a buy link for the numbers above: replacement schedule and reorder. The interval comparison by brand: calculator.
Cleaner and test strips
Hose rinse and soak steps are in how to clean a cartridge. Named cleaners and strips are in filter cleaners and test strips.
Filter cleaner and test strips
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Leisure Time O Filter Clean Cartridge Cleaner Listing title: cartridge cleaner, 32 fl oz.
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SpaGuard Filter Cleaner Listing title: filter cleaner for spas and hot tubs, 1 quart.
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AquaChek SPA 6-in-1 Test Strips Listing title: reads total bromine, total chlorine, free chlorine, pH, total alkalinity and total hardness.
Unicel C-4326 Listing we opened and checked. Match the diameter, length and both fittings on this page before you order. The price is on Amazon; we do not print one.
Sources
- PDC Spas (manufacturer filter guide, 2025): Luxury, Premium, SE and LX, 1990–present: FLT-201TL, 25 sq ft, 5" × 13-5/16", 2-1/8" holes, Unicel C-4326 (PDF)
- Unicel 2026 Replacement Guide: PDC Spas block, PDF p.47 (printed p.43): C-4326, 4-15/16" × 13-5/16", 25 sq ft, 3 oz. Spec table PDF p.9 (printed p.5): 106 pleats, 2-1/8" open ends. C-4625 is the 4 oz cartridge of the same size. (PDF)
- Pleatco 2023 Catalog: Spec table PDF p.32: PRB25-IN, 5" × 13-5/16", 3 oz, 25 sq ft. Cross-reference PDF p.47: C-4326 = PRB25-IN. (PDF)
- Filbur Catalog & Reference Guide: Size table PDF p.9 (printed p.17): FC-2375 = C-4326. PDC section printed p.45: FC-2370 printed as C-4325. (PDF)
Not in sources: Diameter 5" (PDC, Pleatco) vs 4-15/16" (Unicel, Filbur). Filbur’s PDC section prints C-4325 on the FC-2370 row; its size table prints FC-2370 as C-4625 and FC-2375 as C-4326..