Darlly 50406 Spa Filter Cartridge
Replaces Pleatco PFF42TC-P4
- Diameter × length
- 5-3/8" × 9-1/2"
- Filter area
- 40 sq ft
- End caps
- Closed w/ string loop / 1-1/2" MPT
- Per filter
- 1 cartridge
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 50406 is a 40 sq ft spa filter cartridge, 5-3/8" x 9-1/2". It fits the Watkins, Freedom Spa (303279). It replaces Pleatco PFF42TC-P4 and Watkins / Hot Spring 303279.
Specifications
| Darlly part number | 50406 |
|---|---|
| Outside diameter | 5-3/8" |
| Length | 9-1/2" |
| Top end cap | Closed w/ string loop |
| Bottom end cap | 1-1/2" MPT |
| Filter area | 40 sq ft |
| Type | Spa |
| Blue antimicrobial version | 50406M |
| Darlly description | Watkins, Freedom Spa(303279) FC-2402 |
Cross-reference
| Brand | Part numbers Darlly 50406 replaces |
|---|---|
| Pleatco | PFF42TC-P4 |
| OEM and other numbers | Watkins / Hot Spring 303279 |
Filters it fits
| Filter | Cartridges per filter | OEM cartridge number |
|---|---|---|
| Watkins, Freedom Spa (303279) | 1 | 303279 |
Questions
- What Darlly cartridge replaces Pleatco PFF42TC-P4?
- Darlly 50406 replaces Pleatco PFF42TC-P4.
- What size is Darlly 50406?
- Darlly 50406 is 5-3/8" in outside diameter and 9-1/2" long, with 40 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.