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817-4035 spa filter equivalents
Part number 817-4035 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.
Waterway Plastics 4CH-935 cartridge (OEM 817-4035), 4-15/16" (125 mm) × 9-1/4" (235 mm), 35 sq ft. Unicel 4CH-935, Pleatco PWW35L.
Unicel 4CH-935
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| OEM | 817-4035 |
|---|---|
| Unicel | 4CH-935 |
| Pleatco | PWW35L |
| Filbur | FC-0170 |
| Size | 4-15/16" (125 mm) × 9-1/4" (235 mm), 35 sq ft |
Sources
- Unicel 2026 Replacement Guide: Waterway list PDF p.64: 817-4035 = 4CH-935, 4-15/16" x 9-1/4", 35 sq ft. Spec table PDF p.8: 219 pleats, 2" female SAE, standpipe note. (PDF)
- Waterway Plastics Service Logic cartridge table: Fetched 2026-11-09: 817-4035, 35 sq ft, 4-15/16" x 9-1/4", SAE thread (web page)
- Pleatco 2023 Catalog: Spec table PDF p.32: PWW35L, OEM 817-4035, 5" x 8-1/2", 35 sq ft. Cross-reference PDF p.47: 4CH-935 = PWW35L. (PDF)
- Filbur Catalog & Reference Guide: Waterway section PDF p.28: FC-0170, OEM 817-4035, 30 sq ft, Unicel N/A (PDF)
Not in sources: Length 9-1/4" (Unicel, Waterway, Filbur) vs 8-1/2" (Pleatco). Area 35 vs Filbur's 30. Filbur prints no Unicel number on the 817-4035 row. Thread 2" female SAE (Unicel) vs 1-1/2" female SAE (Pleatco)..
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