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.
Cal Spas spa filter (C-4950)
Cal Spas
Replacement numbers
Unicel C-4950, Pleatco PRB50-IN
Fits Cal Spas.
Diameter 4-15/16" (125 mm)Length 13-5/16" (338 mm)50 sq ftUnicel C-4950
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| Unicel | C-4950 |
|---|---|
| Pleatco | PRB50-IN |
| Filbur | FC-2390 |
| 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. 50 sq ft media.
For Cal Spas, C-4950 cartridge sits in Cal Spas. The cross-reference prints Unicel C-4950; Pleatco PRB50-IN; Filbur FC-2390. 4-15/16" across, 13-5/16" long, top 2-1/8" / open, bottom 2-1/8" / open, 50 sq ft.
Hold C-4950 next to 5CH-502 differs by Unicel 5CH-502, Pleatco PPM50SC-F2M, Filbur FC-0195, 5-3/16" diameter, 12-1/2" long, top bar handle, bottom 2” male thread/MPT, OEM FIL11100202, note says Unicel prints OEM FIL11100202 on its own line between 5CH-502 and 5CH-752. Two Cal Spas parts retailers resolve it: Hot Tub Outpost lists Cal Spas FIL11100202 as a 50 sq ft cartridge, 12-1/2" long with a handle top and 2" MPT bottom, that replaces FIL11100200 and FIL11100201 and crosses to Unicel 5CH-502 and Pleatco PPM50SC-F2M; Wizard of Spas lists FIL11100202 (and FIL11100201) as the Cal Spas 50 sq ft cartridge with Filbur FC-0195M. Hot Tub Outpost prints the diameter as 5-1/8" (Unicel and Filbur: 5-3/16") and gives the Filbur number as FC-0196, which the Filbur catalog assigns to the 35 sq ft 5CH-352; the Filbur match shown here is the catalog's own FC-0195.; C-5374 differs by Unicel C-5374, Pleatco PLBS75, Filbur FC-2971, 5-5/16" diameter, 14-13/16" long, 75 sq ft, note says Filbur lists its FC-2971 equivalent at 5-5/16" x 14-11/16", 65 sq ft.
Left blank on purpose: no model/model-year fitment in sources; Unicel lists no OEM part number for this brand entry.
Source locations for this Cal Spas row: Unicel 2026 Replacement Guide on C-4950 (OEM cross reference (Cal Spas section), PDF p.30 (printed p.26); spec table PDF p.9 (printed p.5)). Pleatco 2023 Catalog on C-4950 (Unicel-to-Pleatco cross reference, PDF p.47). Filbur Catalog & Reference Guide on C-4950 (Product by Pool/Spa Manufacturer (OEM), Cal Spas, printed p.29 (PDF p.15)).
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-4950 number is also on the Caldera, Jacuzzi, Sundance, Beachcomber, Coleman Spas pages.
Other Cal Spas cartridges
- 5CH-502 cartridge (OEM FIL11100202), 5-3/16" (132 mm) × 12-1/2" (318 mm)
- C-5374 cartridge, 5-5/16" (135 mm) × 14-13/16" (376 mm)
- 5CH-752 cartridge, 5-3/16" (132 mm) × 16-1/8" (410 mm)
- 4CH-252 cartridge (OEM FIL11100303), 4-5/8" (117 mm) × 8" (203 mm)
- 4CH-19 cartridge (OEM FIL11100305), 4-5/8" (117 mm) × 4-5/8" (117 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.
-
AquaChek SPA 6-in-1 Test Strips Listing title: reads total bromine, total chlorine, free chlorine, pH, total alkalinity and total hardness.
Unicel C-4950 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
- Unicel 2026 Replacement Guide: OEM cross reference (Cal Spas section), PDF p.30 (printed p.26); spec table PDF p.9 (printed p.5) (PDF)
- Pleatco 2023 Catalog: Unicel-to-Pleatco cross reference, PDF p.47 (PDF)
- Filbur Catalog & Reference Guide: Product by Pool/Spa Manufacturer (OEM), Cal Spas, printed p.29 (PDF p.15) (PDF)
Not in sources: no model/model-year fitment in sources; Unicel lists no OEM part number for this brand entry.