Part reference

Pentair R173573

The Pentair R173573 is a replacement pool filter cartridge for the Clean & Clear Plus 320 filter system.

R173573 is the Pentair part number for the single cartridge that fits the Clean & Clear Plus 320. It is the number most current Pentair paperwork uses for one cartridge, and it replaces the older Pac Fab number 178580. When you buy the complete set of four from Pentair, that set is catalogued as 179134, but each cartridge inside it is an R173573.

Specifications

Length	20 1/16 in
Outer diameter	7 in
Top opening	3 in
Bottom opening	3 in
Filtration area	80 sq ft
Media	4 oz polyester

How to verify this is the right cartridge

If R173573 is printed on your cartridge end cap or listed on your filter's label, this is the correct part. It is an OEM Pentair number, so a match here is definitive.

If you cannot read the cap, measure: 20 1/16 inches long, 7 inches in outer diameter, 3 inch openings top and bottom. Those confirm the cartridge whether or not any number survives.

R173573 and 178580 frequently appear together on the same label. That is expected. R173573 is the Pentair number and 178580 is the older Pac Fab number for the same single cartridge, not two separate parts.

How many cartridges does my filter take

The Clean & Clear Plus 320 holds four cartridges. R173573 is a single, so a complete replacement is four. Pentair sells that full set under the number 179134.

Replace all four at once. A single new cartridge among three worn ones carries uneven load and wears faster.

Cross-reference

R173573 is the same cartridge as the numbers below. Any of these fits the Clean & Clear Plus 320:

Brand	Part number
Unicel	C-7470
Pleatco	PCC80
Filbur	FC-1976
Pentair OEM (set of 4)	179134
Pentair OEM (single)	R173573
Pentair / Pac Fab (single)	178580
Pentair OEM	817-0081
Aladdin	18005
Excel Filters	XLS-720
Baleen	AK-60433
Darlly	70804
Unicel (4-pack)	C-7470-4
Pleatco (4-pack)	PCC80-PAK4
Pleatco (EC)	PCC80-EC
Filbur (4-pack)	FC-6465