Darlly 51001 Filter Cartridge
Replaces Unicel C-5399
- Diameter × length
- 5-7/8" × 25-3/4"
- Filter area
- 100 sq ft
- End caps
- semi-circular Handle / male slip fitting w/ molded o-ring
Pool and spa businesses in Florida, Georgia, South Carolina, Alabama, Mississippi, Louisiana and Texas order through their Grit Game rep. Everywhere else, contact Darlly Filtration directly.
Darlly 51001 is a 100 sq ft filter cartridge, 5-7/8" x 25-3/4". It replaces Unicel C-5399.
Specifications
| Darlly part number | 51001 |
|---|---|
| Outside diameter | 5-7/8" |
| Length | 25-3/4" |
| Top end cap | semi-circular Handle |
| Bottom end cap | male slip fitting w/ molded o-ring |
| Filter area | 100 sq ft |
| Darlly description | Seasonmaster Model 141 before 1994) |
Cross-reference
| Brand | Part numbers Darlly 51001 replaces |
|---|---|
| Unicel | C-5399 |
Other Darlly cartridges the same size
Same diameter and length. Check the end caps and area before swapping.
Questions
- What is the Darlly replacement for Unicel C-5399?
- Darlly 51001 replaces Unicel C-5399. Both are 5-7/8" in diameter and about 25-3/4" long.
- What size is Darlly 51001?
- Darlly 51001 is 5-7/8" in outside diameter and 25-3/4" long, with 100 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.