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PWK35B spa filter equivalents
Part number PWK35B 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.
Hot Spring C-6355 cartridge (OEM 1642301-1), 6" (152 mm) × 14" (356 mm), 75 sq ft. Unicel C-6355, Pleatco PWK35B.
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| OEM | 1642301-1 |
|---|---|
| Unicel | C-6355 |
| Pleatco | PWK35B |
| Filbur | not listed |
| Size | 6" (152 mm) × 14" (356 mm), 75 sq ft |
Sources
- Unicel 2026 Replacement Guide: OEM cross reference (Hot Spring section), PDF p.39 (printed p.35); spec table PDF p.12 (printed p.8) (PDF)
- Leisure Time Inc. (Hot Spring/Caldera dealer): Compatibility section: model and model-year list; Specifications: part 78161, alternate part number 1642301-1, 50 sq ft, length 14 in, OD approx. 6-1/4 in, open 2 in top and bottom (web page)
- Pleatco 2023 Catalog: spec table PDF p.33 (Watkins Hot Spring Spas, 6 3/8 x 14, 1-15/16 / 1-15/16, 35 sq ft, OEM 1642301-1 = PWK35B) (PDF)
Not in sources: sq ft rating differs between Unicel (75), the dealer listing for 78161 (50) and Pleatco PWK35B (35); no Filbur equivalent found in Filbur catalog.
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