# 10 Inch Water Filter Cartridge Compatibility: Which 10 x 2.5 in Cartridges Fit a Standard Housing

> A standard 10 in housing takes any 10 x 2.5 in DOE cartridge: Pentek P5 sediment at 2.38 x 9.88 in, CBC-10 carbon block at 2.88 x 9.75 in, on a #237 O-ring.

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| Source | https://ownerspec.com/water/parts/10-inch-standard-water-filter-cartridge-compatibility/ |
| Publisher | OwnerSpec (https://ownerspec.com/) |
| Published | 2026-09-12 |
| Updated | 2026-09-12 |
| Facts verified | 2026-09-12 |
| Disclosure | Contains affiliate links. OwnerSpec may earn a commission at no cost to the reader. |

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## Short answer

A standard 10 inch water filter cartridge is a 10 x 2.5 in nominal double open end (DOE) cartridge, and any housing built for that format takes it regardless of media. Pentair's Pentek Slim Line housing sheet (310050) lists its 10 in housings as compatible with DOE filters, sealed on a #237 EPDM O-ring and rated to 125 psi (8.6 bar). The cartridge is shorter than its name: Pentair's P Series sheet (310060) lists the P5 spun polypropylene sediment cartridge at 2.38 x 9.88 in, 5 micron nominal, 0.2 psi drop at 5 gpm, and its CBC Series sheet (310078) lists the CBC-10 carbon block at 2.88 x 9.75 in, 0.5 micron nominal, over 20,000 gallons at 1 gpm for chlorine taste and odor. Spun polypropylene, string wound, pleated, carbon block and granular carbon all fit the same sump. The spec that must match is the format, 10 in DOE; the media and micron rating are the choice you make.

## Fact sheet

- **Answer:** A standard 10 in housing takes any 10 x 2.5 in nominal DOE cartridge. Pentair's Pentek sheets list the P5 sediment cartridge at 2.38 x 9.88 in and the CBC-10 carbon block at 2.88 x 9.75 in, both sealing on the Slim Line housing's #237 EPDM O-ring, so the media changes while the format stays the same.
- **Applies to:** 10 x 2.5 in standard housing
- **Compatibility basis:** Pentair Pentek Traditional Slim Line housing sheet 310050 and the Pentek P Series (310060), CBC Series (310078), NCP Series (310069) and GAC Series (310070) cartridge spec sheets
- **Assumptions:** Fit is documented only within Pentair's own Slim Line housings and Pentek cartridges. Culligan, iSpring and generic clear housings are sold for the same 10 in DOE format, but no maker sheet for them was reached this session, so their O-ring and maximum diameter are not confirmed.; Figures for A.O. Smith, Membrane Solutions, ICEPURE and PUREPLUS cartridges come from their Amazon listing titles, not a manufacturer document.
- **Method:** Cartridge dimensions, micron ratings, pressure drops and capacities taken directly from Pentair's Pentek spec sheets; consumer-brand sizes read from each listing title; nothing was measured or tested.
- **Primary source:** [Pentair Pentek Traditional Slim Line Series Filter Housings Spec Sheet 310050 (PDF)](https://www.pentair.com/content/dam/extranet/nam/filtration/pentek/residential/spec-sheets/english/310050-pentek-slim-line-spec-sheet.pdf) (manufacturer or vendor document)
- **Facts verified:** 2026-09-12
- **Last updated:** 2026-09-12
- **Canonical URL (cite this):** https://ownerspec.com/water/parts/10-inch-standard-water-filter-cartridge-compatibility/

If the housing cap says 4.5 in or Big Blue, leave now: that is the [Culligan HF-360 and WH-HD200-C page](/water/parts/culligan-hf-360-wh-hd200-replacement-filters/) or the [20 inch Big Blue page](/water/parts/20-inch-big-blue-cartridge-compatibility/), and nothing below fits either.

## Which cartridges fit a standard 10 in housing?

A double open end (DOE) cartridge is open at both ends and seals on the housing's end caps, which is why the media can change without the housing changing. A [nominal micron rating](/water/calculators/micron-rating-picker/) is the maker's stated percentage of particles removed at that size, not an absolute cut-off. Every figure in the first table is from Pentair's own Pentek spec sheets; nothing was measured.

| Cartridge | Family | Part no. | Dimensions (maker's) | Micron (nominal) | Pressure drop or capacity (maker's figure) | Source |
|---|---|---|---|---|---|---|
| Pentek P5 | Spun polypropylene sediment | 155014-43 | 2.38 x 9.88 in | 5 | 0.2 psi at 5 gpm; no capacity published | Pentair P Series sheet 310060 |
| Pentek CBC-10 | Carbon block (CTO) | 155162-43 | 2.88 x 9.75 in | 0.5 | Under 20 psi at 1 gpm; over 20,000 gallons at 1 gpm, chlorine taste and odor | Pentair CBC Series sheet 310078 |
| Pentek NCP-10 | Pleated, carbon-impregnated | 155367-43 | 2.50 x 9.75 in | 10 | 2 psi at 3 gpm; 225 gallons at 1 gpm, chlorine taste and odor | Pentair NCP Series sheet 310069 |
| Pentek GAC-10 | Granular activated carbon | 155109-43 | 2.88 x 9.75 in | Not rated | 7.0 psi at 1.0 gpm; 5,000 gallons at 1.0 gpm, chlorine taste and odor | Pentair GAC Series sheet 310070 |

Pentair's P, CBC and GAC sheets state their listed models are certified to NSF/ANSI 42 for material requirements only, listed per the maker's page and not checked against the NSF database. The NCP sheet shows no certification, and the CBC-10 and GAC-10 capacity figures are footnoted as not NSF-tested.

The consumer brands below sell the same 10 x 2.5 in format. No maker spec sheet for any of them was reached this session, so the only figures are the ones in each Amazon listing title.

| Cartridge | Family | Size and rating (per the listing title) | Pack (per the listing) |
|---|---|---|---|
| A.O. Smith AO-WH-PREV-R2 | Spun sediment | 2.5 x 10 in, 5 micron | 2 |
| Membrane Solutions WPP-F10-5 | String wound sediment | 10 x 2.5 in, 5 micron | 6 |
| ICEPURE CTO | Carbon block (CTO) | 2.5 x 10 in, 1 micron | 4 |
| PUREPLUS CTO10 | Carbon block (CTO) | 2.5 x 10 in, 1 micron | 4 |

A string wound cartridge is yarn wound over a core, the cheapest sediment media. Pentair's WP Series sheet for that family was not reachable this session, so it carries no maker figure here.

## Which housings take a 10 in cartridge?

Pentair's Slim Line sheet is the only housing document read this session that prints the numbers that decide fit. The other rows repeat the retail listing.

| Housing | Port | O-ring | Max pressure | Cartridge format | Source |
|---|---|---|---|---|---|
| Pentek Traditional Slim Line 10 | 1/4, 3/8 or 1/2 in NPT | #237 EPDM, face seal | 125 psi (8.6 bar) | 10 in DOE | Pentair Slim Line sheet 310050 |
| Culligan WH-S200-C | 3/4 in, per the listing title | Not stated on the listing | Not stated on the listing | Compatible with P5, CW-F, CW-MF and S1A-D, per the listing | Amazon listing only; not on culligan.com's current product pages |
| iSpring and generic clear housings | Varies | Not confirmed | Not confirmed | Sold for 10 in DOE | No maker page reached this session |

The #237 O-ring is confirmed for Pentek's Slim Line only. Do not order one for a Culligan or a generic housing on the strength of this page; measure the old ring or read the housing's manual.

Three live listings carry 10 in in the name but are 4.5 in in diameter per their listing titles, and will not go into a 2.5 in sump: iSpring FP15B (5 micron), A.O. Smith AO-WH-PREL-RP (20 micron) and PUREPLUS PP10BB-CC (sediment and carbon combo).

## How often do they need replacing?

Pentair publishes a capacity for the carbon families and none for sediment: a P5 is finished when the pressure drop across it climbs, and the sheet's 0.2 psi at 5 gpm is a starting point, not a service life. The carbon figures are the CBC-10 at over 20,000 gallons, the NCP-10 at 225 gallons and the GAC-10 at 5,000 gallons, each at 1 gpm for chlorine taste and odor, the last footnoted as the maker's internal test.

A higher [chlorine residual](/water/guides/chlorine-chloramine-city-water/) spends any carbon cartridge sooner, and [sediment or turbidity](/water/guides/sediment-turbidity-well-water/) ahead of it shortens every interval. The A.O. Smith listing calls its cartridge a 3-month filter, a retailer figure with no gallon basis. Run the [whole house filter flow rate calculator](/water/calculators/whole-house-filter-flow-rate-calculator/) before putting a 10 in housing on a whole-house line: at 1 gpm rated flow the carbon block is an under-sink part.

**Which cartridge to order**

The Pentek P5 is 5 micron nominal, not absolute, and Pentair publishes no capacity for it; its case is a published pressure drop, a 2.38 in diameter that clears any 10 in DOE sump, and a material certification the generic packs do not print. Skip it if you need an absolute-rated cut for a specific micron size, since nominal is a percentage claim, not a guarantee.

The CBC-10 carries the published 20,000 gallon chlorine figure but ties the GAC-10 for the least flow of the four families, under 20 psi at 1 gpm on its own sheet, so skip it on a gritty well unless a sediment cartridge sits ahead of it.

The Membrane Solutions string wound 6-pack has only the listing title behind its 5 micron claim; buy it for a gritty well and replace it on sight rather than on a schedule, since no maker or listing publishes a capacity for this SKU, and skip every cartridge here if the water is orange or smells of sulfur, since the [iron](/water/guides/iron-in-well-water/) and [rotten egg smell](/water/guides/rotten-egg-smell-well-water/) guides carry those limits.

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## The picks

- **Pentek P5**: Sediment stage, any 10 in housing: the default (2.38 x 9.88 in, 5 micron nominal spun polypropylene; 0.2 psi at 5 gpm; NSF/ANSI 42 material, listed per the maker's sheet) Amazon: https://www.amazon.com/dp/B0C2SKZJG3/?tag=ownerspec-20
- **Pentek CBC-10**: Carbon stage, city water with a chlorine residual (2.88 x 9.75 in carbon block, 0.5 micron nominal; under 20 psi at 1 gpm; over 20,000 gallons chlorine taste and odor, maker's figure) Amazon: https://www.amazon.com/dp/B000UQPONM/?tag=ownerspec-20
- **Membrane Solutions string wound 6-pack**: Well water with visible grit, changed often (10 x 2.5 in string wound, 5 micron per the listing title; no maker spec sheet reached this session) Amazon: https://www.amazon.com/dp/B082PXRJBZ/?tag=ownerspec-20
- **Culligan WH-S200-C housing**: No housing yet: a clear 10 in sump with a 3/4 in port (3/4 in inlet and outlet, pressure relief valve, ships with one cartridge, all per the listing title; compatible with P5, CW-F, CW-MF and S1A-D per the listing) Amazon: https://www.amazon.com/dp/B01JIRHRBK/?tag=ownerspec-20

## Frequently asked questions

### How long is a 10 inch water filter cartridge actually?

Shorter than 10 in. Pentair's P Series sheet (310060) lists the P5 spun polypropylene cartridge at 2.38 x 9.88 in maximum, and its CBC Series sheet (310078) lists the CBC-10 carbon block at 2.88 x 9.75 in. The housing's end caps and O-ring take up the difference, which is why both lengths seal in the same 10 in Slim Line sump.

### What O-ring does a standard 10 inch filter housing use?

Pentair's Traditional Slim Line housing sheet (310050) lists a #237 EPDM face-seal O-ring for its 10 in housings. That number is confirmed only for Pentek's own Slim Line line. Culligan, iSpring and generic clear housings are sold for the same 10 in DOE format, but no maker sheet for them was reached this session, so their O-ring size is not stated here.

### What does NSF/ANSI Standard 42 certify on these cartridges?

Material safety, not contaminant reduction. Pentair's P, CBC and GAC sheets each state their listed models are tested and certified by NSF International to NSF/ANSI Standard 42 for material requirements only. The CBC-10 capacity of over 20,000 gallons and the GAC-10 figure of 5,000 gallons are separately footnoted as not NSF-tested, and the NCP-10 sheet shows no certification.

### How much water can a 10 inch carbon block cartridge treat before replacement?

Pentair's CBC Series sheet (310078) lists the CBC-10 at over 20,000 gallons at 1 gpm for chlorine taste and odor, a figure the sheet flags as not NSF-tested. The same sheet holds the CBC-10 to under 20 psi pressure drop at 1 gpm, tied with the GAC-10 for the lowest flow of the four Pentek families, so a high chlorine residual or a fast tap spends it sooner.

### What is the difference between a pleated and a spun polypropylene sediment cartridge?

The cut and the second job. Pentair's NCP Series sheet (310069) rates the pleated, carbon-impregnated NCP-10 at 10 micron nominal and 2 psi at 3 gpm, with 225 gallons at 1 gpm for chlorine taste and odor. Its P Series sheet (310060) rates the spun P5 at 5 micron nominal and 0.2 psi at 5 gpm with no chlorine claim at all.


## Sources

- [Pentair Pentek Traditional Slim Line Series Filter Housings Spec Sheet 310050 (PDF)](https://www.pentair.com/content/dam/extranet/nam/filtration/pentek/residential/spec-sheets/english/310050-pentek-slim-line-spec-sheet.pdf) (manufacturer or vendor document)
- [Pentair Pentek P Series Spun-Bonded Polypropylene Cartridges Spec Sheet 310060 Rev E (PDF)](https://www.pentair.com/content/dam/extranet/web/nam/pentek/spec-sheets/310060-pentek-p-series-spec-sheet.pdf) (manufacturer or vendor document)
- [Pentair Pentek CBC Series Carbon Block Cartridges Spec Sheet 310078 Rev G (PDF)](https://www.pentair.com/content/dam/extranet/web/nam/pentek/spec-sheets/310078-pentek-cbc-series-spec-sheet.pdf) (manufacturer or vendor document)
- [Pentair Pentek NCP Series Carbon-Impregnated Pleated Cartridges Spec Sheet 310069 Rev D (PDF)](https://www.pentair.com/content/dam/extranet/web/nam/pentek/spec-sheets/310069-pentek-ncp-series-spec-sheet.pdf) (manufacturer or vendor document)
- [Pentair Pentek GAC Series Granular Activated Carbon Cartridges Spec Sheet 310070 Rev D (PDF)](https://www.pentair.com/content/dam/extranet/web/nam/pentek/spec-sheets/310070-pentek-gac-series-spec-sheet.pdf) (manufacturer or vendor document)

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Citation: OwnerSpec, "10 Inch Water Filter Cartridge Compatibility: Which 10 x 2.5 in Cartridges Fit a Standard Housing", https://ownerspec.com/water/parts/10-inch-standard-water-filter-cartridge-compatibility/, facts verified 12 September 2026.
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