Darlly 40504 Spa Filter Cartridge
Replaces Unicel C-4350 (discontinued)
- Diameter × length
- 4-5/8" × 23-3/4"
- Filter area
- 50 sq ft
- End caps
- 2-1/16" Open / 2-1/16" Open
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 40504 is a 50 sq ft spa filter cartridge, 4-5/8" x 23-3/4". It replaces Unicel C-4350 (discontinued).
Specifications
| Darlly part number | 40504 |
|---|---|
| Outside diameter | 4-5/8" |
| Length | 23-3/4" |
| Top end cap | 2-1/16" Open |
| Bottom end cap | 2-1/16" Open |
| Filter area | 50 sq ft |
| Type | Spa |
| Darlly description | Grecian Spa |
Cross-reference
| Brand | Part numbers Darlly 40504 replaces |
|---|---|
| Unicel | C-4350 (discontinued) |
Questions
- What is the Darlly replacement for Unicel C-4350?
- Darlly 40504 replaces Unicel C-4350. Both are 4-5/8" in diameter and about 23-3/4" long.
- What size is Darlly 40504?
- Darlly 40504 is 4-5/8" in outside diameter and 23-3/4" long, with 50 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.