Darlly 51351 Spa Filter Cartridge
Replaces Unicel C-5351 · Pleatco PCST120 · Filbur FC-2976
Darlly 51351 is a 135 sq ft spa filter cartridge, 5-5/16" x 30-1/8". It replaces Unicel C-5351, Pleatco PCST120 and Filbur FC-2976.
Specifications
| Darlly part number | 51351 |
|---|---|
| Outside diameter | 5-5/16" |
| Length | 30-1/8" |
| Top end cap | 2-1/8" Open |
| Bottom end cap | 2-1/8" Open |
| Filter area | 135 sq ft |
| Type | Spa |
| Darlly description | Water. Coast Spas |
Cross-reference
| Brand | Part numbers Darlly 51351 replaces |
|---|---|
| Unicel | C-5351 |
| Pleatco | PCST120 |
| Filbur | FC-2976 |
Questions
- What is the Darlly replacement for Unicel C-5351?
- Darlly 51351 replaces Unicel C-5351. Both are 5-5/16" in diameter and about 30-1/8" long.
- What Darlly cartridge replaces Pleatco PCST120?
- Darlly 51351 replaces Pleatco PCST120.
- What size is Darlly 51351?
- Darlly 51351 is 5-5/16" in outside diameter and 30-1/8" long, with 135 sq ft of filter area.
Cross-reference checked October 21, 2026 against Unicel's 2026 Replacement Guide, Pleatco's catalog (updated September 2025), filbur.com and darllyfilter.com. A competitor number is listed only when that brand's own data pairs it with the same cartridge size. Always compare the size and end caps of your old cartridge before ordering.
Brand names and part numbers are trademarks of their respective owners and are shown only to identify compatible replacements. Darlly Filtration is not affiliated with or endorsed by them. Cross-reference by The Grit Game, Darlly's sales agency.