Pleatco PMT27.5 = Unicel C-4301 = Filbur FC-1616 = Filbur FC-1610
28 sq ft hot tub filter, 5" diameter × 14-7/8" long. Top: 2-1/8" open · Bottom: 2-1/8" open. Pleatco application: Sonfarrel 25-220122, Martec.
Interchangeable cartridges
- Unicel C-4301 confirmed by: Pleatco p.47 (Unicel to Pleatco cross reference) Unicel p.9 (Cartridges by series (dimensional listing))
- Filbur FC-1616 confirmed by: Pleatco p.48 (Filbur to Pleatco cross reference)
- Filbur FC-1610 confirmed by: Filbur p.33 (Reverse cross reference (Unicel to Filbur)) Filbur p.9 (Dimensional cartridge listing)
Check before you order
- Filbur FC-1610 rates it 25 sq ft (vs 28 sq ft); filter area ratings differ by maker.
- Listed by Filbur's reverse cross reference only; Pleatco maps this cartridge to a different Filbur number.
Published dimensions, side by side
Each manufacturer measures a little differently. Compare these with your old cartridge.
| As published by | Pleatco PMT27.5 source | Unicel C-4301 source | Filbur FC-1616 source |
|---|---|---|---|
| Outside diameter | 5" | 4-15/16" | 4-15/16" |
| Length | 14-7/8" | 14-7/8" | 14-7/8" |
| Top end | 2-1/8" open | 2-1/8" / open | 2-1/8" open |
| Bottom end | 2-1/8" open | 2-1/8" / open | 2-1/8" open |
| Filter area | 28 sq ft | 28 sq ft | 25 sq ft |
| Pleats | not listed | 106 | not listed |
| Media weight | 3 oz/yd² | 3 oz/yd² | not listed |
Where to buy
Search any retailer for C-4301 or PMT27.5 or FC-1616 or FC-1610. These are the same cartridge under different brand names.
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OEM part numbers this cartridge replaces
As printed in the cited aftermarket catalogs. Match the number on your old cartridge or in your spa manual exactly.
| OEM number | Listed in |
|---|---|
220122 | Pleatco p.32: OEM part # column Unicel p.56: OEM cross reference: Sonfarrel |
ELE-25 | Pleatco p.32: OEM part # column |
ELE-25 (top load) | Unicel p.26: OEM cross reference: Advantage Mfg. |
CL-2200 | Unicel p.44: OEM cross reference: Martec |
220132 | Unicel p.56: OEM cross reference: Sonfarrel |
Hot tub brands that use it
From the spa-manufacturer cross reference in the Unicel 2026 Replacement Guide. A brand may use several sizes, so check your measurements.
- Advantage Mfg. (OEM ELE-25 (top load)) Unicel p.26
- Martec (OEM CL-2200) Unicel p.44
- Nordic Hot Tubs Unicel p.46
- Sonfarrel (OEM 220122, 220132) Unicel p.56
- Thermo Spas of Connecticut Unicel p.60
FAQ
What is the Unicel equivalent of Pleatco PMT27.5?
The catalogs cross-reference Pleatco PMT27.5 to Unicel C-4301.
What is the Filbur equivalent of Pleatco PMT27.5?
The catalogs list Filbur FC-1616, FC-1610.
What size is the PMT27.5 filter?
Pleatco lists PMT27.5 as 5" outside diameter by 14-7/8" long, top: 2-1/8" open, bottom: 2-1/8" open, 28 sq ft.
Which OEM part numbers does it replace?
Listed OEM numbers: 220122, ELE-25, ELE-25 (top load), CL-2200, 220132.
Sources: Filbur Product Catalog and Reference Guide (2024) · Filbur Product Catalog and Reference Guide (2024) · Pleatco 2023 Catalog & Cross Reference Guide (Pentair) · Pleatco 2023 Catalog & Cross Reference Guide (Pentair) · Pleatco 2023 Catalog & Cross Reference Guide (Pentair) · Unicel 2026 Replacement Guide. Last checked 2026-10-21.