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FC-3638 spa filter equivalents
Part number FC-3638 appears in 1 cross-reference row below. Each row lists the OEM, Unicel and Pleatco numbers that the source documents treat as interchangeable, plus the cartridge size so you can confirm against your old filter.
The same numbers, on one page, are in the cross-reference lookup. A schedule for this part number, and the buy link, are on the replacement schedule and reorder page. Published intervals by brand are in the replace and clean calculator.
Marquis Spas C-5346 cartridge (OEM 20044), 5-3/16" (132 mm) × 14-1/8" (359 mm), 50 sq ft. Unicel C-5346, Pleatco PPM50TC.
Unicel C-5346
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| OEM | 20044 |
|---|---|
| Unicel | C-5346 |
| Pleatco | PPM50TC |
| Filbur | FC-3638 |
| Size | 5-3/16" (132 mm) × 14-1/8" (359 mm), 50 sq ft |
Sources
- Unicel 2026 Replacement Guide: OEM cross reference (Marquis Spas section), PDF p.44 (printed p.40); spec table PDF p.10 (printed p.6) (PDF)
- Filbur Catalog & Reference Guide: Product by Pool/Spa Manufacturer (OEM), Marquis Spas, printed p.43 (PDF p.22) (PDF)
- Marquis Spas (manufacturer filter finder): Filter Finder (series, model years, slip-on/threaded, sq ft, part number): Signature Series 1997–1999, slip-on 50, 20044 (web page)
Not in sources: alternate OEM number differs between Unicel (370-0236) and Filbur (370-217); Marquis's finder gives 20044 only and no dimensions.
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