Pool Filter Lab

Cartridge record

Unicel 5CH-203

Also sold asPleatco PLAS35Filbur FC-0303OnCore OC-508A

cross-checked against 3 sources

Verified specifications

The selected value is shown first. Expand any row to compare the source values retained by the dataset.

Cartridge specifications
Outside diameter5-3/8"
Source values
  • unicel 5-3/8"
  • pleatco 5-1/2"
Length7"
Source values
  • unicel 7"
  • pleatco 8-9/16"
Top cap/ semi-circular handle
Source values
  • unicel / semi-circular handle
  • pleatco Handle
Bottom cap/ 3" male thread/MPT
Source values
  • unicel / 3" male thread/MPT
  • pleatco 3” NPT
Pleats235
Source values
  • unicel 235
Filter area20 sq ft
Source values
  • unicel 20
  • pleatco 30
Media weight3 oz
Source values
  • unicel 3
  • pleatco 3

Equivalent part numbers

Match the complete printed string. Similar-looking part numbers can describe different end caps or lengths.

Cross-reference equivalents
BrandPart numberVerification
Unicel5CH-203cross-checked against 3 sources
PleatcoPLAS35cross-checked against 2 sources
FilburFC-0303single-source
OnCoreOC-508Asingle-source

Known equipment fits

Fitments are source-attributed. Confirm the housing model and cartridge measurements before ordering.

Filter and spa fitments
BrandModelOEM partSource
LA Spas / Advanced Spa DesignReplacement for bag filter—pleatco single-source
LA Spas——unicel single-source
Unicel20 sq.ft. top load—unicel single-source

Source notes

Dimension neighbors

Records with the same outside diameter and a different length appear first, followed by the closest diameters. End-cap details still need to match.

5CH-37

5-5/16" × 9"

cross-checked against 2 sources

5CH-45

5-5/16" × 10"

cross-checked against 3 sources

C-5345

5-5/16" × 10-1/8"

cross-checked against 3 sources

C-5623

5-5/16" × 13-9/16"

single-source

C-5374

5-5/16" × 14-13/16"

cross-checked against 3 sources

Find this cartridge

Outbound retailer searches are provided for convenience; Pool Filter Lab is not the seller.