Fleetguard · HF Hydraulic · return line
HF6721 filter element: specifications & equivalents
The HF6721 is a Fleetguard return-line hydraulic filter element, sized 128.93 × 272.01 mm OD × length, rated at 14 µm class (TWA 14 µm at β=2; 23 µm at β75(c); 25 µm at β200(c) per ISO 16889). Verify against the current manufacturer data sheet before ordering.
Specifications and cross-references are taken from the Fleetguard online catalog API. Where both TWA and Beta ratings are published the conventions differ — verify cleanliness targets, collapse rating and seal configuration against the current Fleetguard data sheet before ordering.
Specification table
| Parameter | Value |
|---|---|
| Filter type | return line |
| Filtration rating | 14 µm |
| Rating basis | nominal |
| Beta ratio | TWA 14 µm at β=2; 23 µm at β75(c); 25 µm at β200(c) per ISO 16889 |
| Outside diameter OD | 128.93 mm |
| Length | 272.01 mm |
| Thread / connection | 1.00 1/2-16 UN-2B |
| End caps | spin-on baseplate with attached gasket |
| Flow direction | outside-in |
| Integral bypass valve | none (housing/valve-dependent) |
| Manufacturer part no. | HF6721 |
| Source catalog | Cummins Filtration / Fleetguard: Fleetguard online product catalog (fleetguard.com) |
| Last verified | 2026-09-28 |
Sources: Cummins Filtration / Fleetguard — Fleetguard online product catalog (fleetguard.com) — accessed 2026-09-28.
Fleetguard® and all model designations are trademarks of their respective owners, used here for identification only — ElementRef is an independent reference site, not an authorized Fleetguard distributor.
Dimensions & series range
| Outside diameter | 128.93 mm (5.076 in) |
| Overall length | 272.01 mm (10.709 in) |
All 129×272 mm interchange elements →
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
|
↔ 034391T1 page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists 034391T1 as an interchange for HF6721. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ 12427392 page in verification queue | UFI | partial | Fleetguard's online catalog lists 12427392 as an interchange for HF6721. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
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↔ 1390702 page in verification queue | UFI | partial | Fleetguard's online catalog lists 1390702 as an interchange for HF6721. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ 178025 page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists 178025 as an interchange for HF6721. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ 26839099 page in verification queue | UFI | partial | Fleetguard's online catalog lists 26839099 as an interchange for HF6721. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ 3600148 page in verification queue | UFI | partial | Fleetguard's online catalog lists 3600148 as an interchange for HF6721. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
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↔ 3I1664 page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists 3I1664 as an interchange for HF6721. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ 40202 page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists 40202 as an interchange for HF6721. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ 4453K84 page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists 4453K84 as an interchange for HF6721. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ 70172 page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists 70172 as an interchange for HF6721. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ 927737 page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists 927737 as an interchange for HF6721. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ 927737B page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists 927737B as an interchange for HF6721. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
| ↔ BT389 | Baldwin Filters | partial | Fleetguard's online catalog lists BT389 as an interchange for HF6721. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
| ↔ BT389 | Baldwin Filters | partial | Baldwin's Form 561 Number-Finder cross-reference lists HF6721 (FLEETGUARD) as replaced by Baldwin BT389. Form/fit listing without published performance data — verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ CA302ACV1 page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists CA302ACV1 as an interchange for HF6721. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
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↔ CSG150P10A page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists CSG150P10A as an interchange for HF6721. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ CSG150P25 page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists CSG150P25 as an interchange for HF6721. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
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↔ ESF22NCC page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists ESF22NCC as an interchange for HF6721. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
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↔ ESF22NCCDP page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists ESF22NCCDP as an interchange for HF6721. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
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↔ F4E07025N page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists F4E07025N as an interchange for HF6721. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
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↔ F4E070DCB page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists F4E070DCB as an interchange for HF6721. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
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↔ FA51110 page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists FA51110 as an interchange for HF6721. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ FC1030 page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists FC1030 as an interchange for HF6721. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ FPE7025N page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists FPE7025N as an interchange for HF6721. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
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↔ FV5880 page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists FV5880 as an interchange for HF6721. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
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↔ GLE25 page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists GLE25 as an interchange for HF6721. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
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↔ H511125M26 page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists H511125M26 as an interchange for HF6721. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
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↔ HC7500SUJ8H page in verification queue | Pall | partial | Fleetguard's online catalog lists HC7500SUJ8H as an interchange for HF6721. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
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↔ HF0672100 page in verification queue | Fleetguard | partial | Fleetguard's online catalog lists HF0672100 as an interchange for HF6721. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ HF0672100JX page in verification queue | Fleetguard | partial | Fleetguard's online catalog lists HF0672100JX as an interchange for HF6721. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ LE10P page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists LE10P as an interchange for HF6721. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ LPS511B06 page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists LPS511B06 as an interchange for HF6721. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ MF0058070 page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists MF0058070 as an interchange for HF6721. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ MFE1601252 page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists MFE1601252 as an interchange for HF6721. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
| ↔ P165880 | Donaldson | partial | Fleetguard's online catalog lists P165880 as an interchange for HF6721. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
| ↔ P550252 | Donaldson | partial | Fleetguard's online catalog lists P550252 as an interchange for HF6721. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ P562205 page in verification queue | Donaldson | partial | Fleetguard's online catalog lists P562205 as an interchange for HF6721. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
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↔ RE101 page in verification queue | STAUFF | partial | Fleetguard's online catalog lists RE101 as an interchange for HF6721. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
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↔ RSE6025N page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists RSE6025N as an interchange for HF6721. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
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↔ RSE7025N page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists RSE7025N as an interchange for HF6721. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
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↔ S59E page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists S59E as an interchange for HF6721. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ SPE6010 page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists SPE6010 as an interchange for HF6721. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ ST6721 page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists ST6721 as an interchange for HF6721. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
| ↔ WD13005X | MANN-FILTER | partial | MANN-FILTER's online catalog lists HF6721 (FLEETGUARD/CUMMINS FILTRATION) as a comparison number for WD13005X. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
| ↔ WD13009X | MANN-FILTER | partial | MANN-FILTER's online catalog lists HF6721 (FLEETGUARD/CUMMINS FILTRATION) as a comparison number for WD13009X. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
| ↔ WD13009X | MANN-FILTER | partial | Fleetguard's online catalog lists WD13009X as an interchange for HF6721. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ WL10103 page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists WL10103 as an interchange for HF6721. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
Interchange levels: full catalog-confirmed drop-in · partial verify parameters · verify manual confirmation required. Links resolve to the equivalent model's specification page where available.
How the HF6721 model number is decoded
- HF6721Fleetguard HF-series hydraulic spin-on filter part number.
- 272.01 mmOverall height.
- 128.93 mmLargest outside diameter.
- 1.00 1/2-16 UN-2BSpin-on mounting thread.
- TWA 14 µm at β=2; 23 µm at β75(c); 25 µm at β200(c) per ISO 16889Published efficiency ratings.
Typical equipment & applications
- Construction, agricultural and industrial hydraulic circuits
- Mobile-equipment hydraulic return and pressure lines
Selection pitfalls — read before you substitute
- A return-line element is not a pressure-line element: return cartridges (BN4HC low-collapse) tolerate roughly 20 bar differential, while BH4HC pressure executions are rated to 210 bar. Installing a low-collapse element in a pressure housing can rupture the media on cold-start spikes.
- This element has no integral bypass — opening pressure is set by the housing’s reusable bypass valve. Confirm the valve setting (commonly 3.4 bar) is present before fitting.
- “10 µm nominal” and “12 µm at β1000” can describe the very same media — one is reported at β≥200, the other at β≥1000 per ISO 16889. Compare ratings at the same Beta test point, not just the printed micron number.
- Nitrile (NBR) seals are standard for mineral hydraulic oil but fail early in some phosphate-ester fluids and at sustained high temperature; verify seal compound against the fluid data sheet (fluorocarbon/Viton executions may be required).
- End-cap geometry and the number/position of O-rings block interchange even when OD and length match — visually compare end caps before fitting, especially with aftermarket cartridges.
Frequently asked questions
What are the dimensions of the HF6721 filter element?
What micron rating does HF6721 use?
What replaces the HF6721 filter element?
How do I read the HF6721 part number?
Is a same-envelope aftermarket element always a drop-in replacement?
How often should a hydraulic return-line element be replaced?
Same-envelope elements from other brands
View full interchange →These 18 catalog element(s) share the 129×272 mm envelope. Envelope match alone does not guarantee interchangeability — compare micron/Beta, seals and collapse rating.
Other models in the HF Hydraulic series
All 2621 →Reviewed & verified by the ElementRef engineering desk against Cummins Filtration / Fleetguard on 2026-09-28. Read our editorial & correction policy.