What is the Darlly replacement for Unicel C-5345?

Darlly 50451 replaces Unicel C-5345. Both are 5-5/16" in diameter and about 10-1/8" long.

What Darlly cartridge replaces Pleatco PLBS50?

Darlly 50451 replaces Pleatco PLBS50, which Pleatco now sells as ULTRA-S10.

What size is Darlly 50451?

Darlly 50451 is 5-5/16" in outside diameter and 10-1/8" long, with 45 sq ft of filter area.

Darlly 50451 Spa Filter Cartridge

Replaces Unicel C-5345 · Pleatco PLBS50 (now ULTRA-S10) · Filbur FC-2970

Darlly 50451 is a 45 sq ft spa filter cartridge, 5-5/16" x 10-1/8". It fits the Rec Warehouse S2/G2 Spa, Rainbow, Waterway. It replaces Unicel C-5345, Pleatco PLBS50 (now ULTRA-S10) and Filbur FC-2970.

Specifications

Darlly part number	50451
Outside diameter	5-5/16"
Length	10-1/8"
Top end cap	2-1/8" Open
Bottom end cap	2-1/8" Open
Filter area	45 sq ft
Type	Spa
Blue antimicrobial version	50451M
Darlly description	Rec Warehouse S2/G2 Spa, Rainbow, Waterway

Cross-reference

Brand	Part numbers Darlly 50451 replaces
Unicel	C-5345
Pleatco	PLBS50 (now ULTRA-S10), ULTRA-S10
Filbur	FC-2970
Hurricane (former brand)	HF5345-01

Filters it fits

Filter	Cartridges per filter
Rec Warehouse S2/G2 Spa, Rainbow, Waterway	1

Questions

What is the Darlly replacement for Unicel C-5345?: Darlly 50451 replaces Unicel C-5345. Both are 5-5/16" in diameter and about 10-1/8" long.
What Darlly cartridge replaces Pleatco PLBS50?: Darlly 50451 replaces Pleatco PLBS50, which Pleatco now sells as ULTRA-S10.
What size is Darlly 50451?: Darlly 50451 is 5-5/16" in outside diameter and 10-1/8" long, with 45 sq ft of filter area.

Where to buy Darlly 50451

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 50451 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.