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FC-3966 spa filter equivalents
Part number FC-3966 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.
Caldera C-8300 cartridge (OEM 74817), 8" (203 mm) × 16-1/2" (419 mm), 100 sq ft. Unicel C-8300, Pleatco not listed.
Unicel C-8300
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| OEM | 74817 |
|---|---|
| Unicel | C-8300 |
| Pleatco | not listed |
| Filbur | FC-3966 |
| Size | 8" (203 mm) × 16-1/2" (419 mm), 100 sq ft |
Sources
- Unicel 2026 Replacement Guide: OEM cross reference (Caldera section), PDF p.30 (printed p.26); spec table PDF p.20 (printed p.16) (PDF)
- Leisure Time Inc. (Caldera dealer): Unicel C-8300 product page: replaces Caldera 74817; Filbur FC-3966 (web page)
- Filbur Catalog & Reference Guide: Caldera section, printed p.30 (PDF p.16), lists FC-3966 at 8" x 16-1/2", 100 sq ft with no OEM number (PDF)
- Leisure Time Inc. (Hot Spring/Caldera dealer): Compatibility section: model and model-year list (web page)
Not in sources: no Pleatco equivalent in Pleatco 2023 cross reference.
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