What is the Darlly replacement for Unicel C-5374?

Darlly 50651 replaces Unicel C-5374. Both are 5-5/16" in diameter and about 14-13/16" long.

What Darlly cartridge replaces Pleatco PLBS75?

Darlly 50651 replaces Pleatco PLBS75.

What size is Darlly 50651?

Darlly 50651 is 5-5/16" in outside diameter and 14-13/16" long, with 65 sq ft of filter area.

Darlly 50651 Spa Filter Cartridge

Replaces Unicel C-5374 · Pleatco PLBS75 · Filbur FC-2971

Darlly 50651 is a 65 sq ft spa filter cartridge, 5-5/16" x 14-13/16". It fits the Rec Warehouse / Leisure Bay S2/G2 Spa 75, Rainbow and Waterway. It replaces Unicel C-5374, Pleatco PLBS75, Filbur FC-2971, Waterway 817-0015 and Pentair R173600.

Specifications

Darlly part number	50651
Outside diameter	5-5/16"
Length	14-13/16"
Top end cap	2-1/8" Open
Bottom end cap	2-1/8" Open
Filter area	65 sq ft
Type	Spa
Blue antimicrobial version	50651M
Darlly description	Rec Warehouse S2/G2 Spa, Rainbow, Waterway

Cross-reference

Brand	Part numbers Darlly 50651 replaces
Unicel	C-5374
Pleatco	PLBS75
Filbur	FC-2971
Hurricane (former brand)	HF5374-01
OEM and other numbers	Waterway 817-0015, Pentair R173600

Filters it fits

Filter	Cartridges per filter	OEM cartridge number
Rec Warehouse / Leisure Bay S2/G2 Spa 75; Rainbow; Waterway (75 sq ft filter)	1	817-0015, R173600

Questions

What is the Darlly replacement for Unicel C-5374?: Darlly 50651 replaces Unicel C-5374. Both are 5-5/16" in diameter and about 14-13/16" long.
What Darlly cartridge replaces Pleatco PLBS75?: Darlly 50651 replaces Pleatco PLBS75.
What size is Darlly 50651?: Darlly 50651 is 5-5/16" in outside diameter and 14-13/16" long, with 65 sq ft of filter area.

Where to buy Darlly 50651

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.

Find your Grit Game rep Contact Darlly Darlly 50651 on darllyfilter.com

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.