Filtrec · Filtrec elements · inline line

FS121B5T125 filter element: specifications & equivalents

Q: What are the dimensions of the FS121B5T125 filter element?

The published envelope is 64 mm OD × 139 mm length (2.520 × 5.472 in). Confirm against the housing drawing before ordering.

Q: What micron rating does FS121B5T125 use?

This element is rated 125 µm (nominal class). Always compare Beta ratings at the same test point: two brands may print different micron numbers for the same physical grade.

The FS121B5T125 is a Filtrec inline-line hydraulic filter element, built with wire-mesh media, sized 64 × 139 mm OD × length, rated at 125 µm class. Verify against the current manufacturer data sheet before ordering.

Envelope OD × L 64 × 139 mm

Filtration rating 125 µm nom.

Media wire-mesh

Line type inline

Catalog verified. Parameters extracted from the manufacturer’s electronic catalog / official interchange document and checked 2026-10-03. Confidence score 0.90.

Dimensions and media grade are taken from Filtrec’s official Cross Navigator, which maps this element to specific competitor part numbers. Filtrec does not publish collapse pressure or seal compound in this API for every code — verify collapse rating, seal execution and bypass setting against the current Filtrec data sheet for the target housing before ordering.

Specification table

Parameter	Value
Filter type	inline line
Media	wire-mesh
Filtration rating	125 µm
Rating basis	nominal
Outside diameter OD	64 mm
Length	139 mm
Integral bypass valve	none (housing/valve-dependent)
Manufacturer part no.	FS121B5T125
Source catalog	Filtrec S.p.A.: Filtrec Cross Navigator
Last verified	2026-10-03

Sources: Filtrec S.p.A. — Filtrec Cross Navigator — accessed 2026-10-03.

Filtrec® and all model designations are trademarks of their respective owners, used here for identification only — ElementRef is an independent reference site, not an authorized Filtrec distributor.

Dimensional drawing

Reference drawing generated from the source values cited on this page — nominal envelope, schematic section, not a manufacturer drawing. The PDF is A3 landscape and vector; the PNG is sized for a WhatsApp preview. Confirm thread, end caps, seal compound and micron/Beta grade against the original element before ordering.

Dimensions & series range

Outside diameter	64 mm (2.520 in)
Overall length	139 mm (5.472 in)

All 64×139 mm interchange elements →

Cross references & equivalents

Equivalent model	Brand	Match level	Note
↔ PT9225	Baldwin Filters	full	Filtrec's official Cross Navigator maps BALDWIN PT9225 to FILTREC FS121B5T125 as a direct replacement, publishing the FILTREC element's OD/ID/height envelope and media grade.
↔ SFE50G125A10 page in verification queue	Aftermarket	full	Filtrec's official Cross Navigator maps HYDAC SFE50G125A10 to FILTREC FS121B5T125 as a direct replacement, publishing the FILTREC element's OD/ID/height envelope and media grade.
↔ HD6008	MANN-FILTER	partial	MANN-FILTER's online catalog lists FS121B5T125 (FILTREC) as a comparison number for HD6008. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting.
↔ HF6251	Fleetguard	partial	Fleetguard's online catalog lists FS121B5T125 as an interchange for HF6251. 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.

Full chart: Filtrec cross reference chart →

How the FS121B5T125 model number is decoded

T125Filtrec internal media grade code (wire-mesh, 125 µm).

Typical equipment & applications

Filtrec aftermarket replacement hydraulic/lube filter element (FS family), form-fit-function cross-referenced in Filtrec's official Cross Navigator.

Selection pitfalls — read before you substitute

“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.

Frequently asked questions

What are the dimensions of the FS121B5T125 filter element?

The published envelope is 64 mm OD × 139 mm length (2.520 × 5.472 in). Confirm against the housing drawing before ordering.

What micron rating does FS121B5T125 use?

This element is rated 125 µm (nominal class). Always compare Beta ratings at the same test point: two brands may print different micron numbers for the same physical grade.

What replaces the FS121B5T125 filter element?

2 catalog-confirmed full match(es) (PT9225, SFE50G125A10); 2 partial match(es) requiring parameter review

Is a same-envelope aftermarket element always a drop-in replacement?

No. Matching OD and length only proves the cartridge fits the bowl. End-cap style, seal compound, micron/Beta rating, collapse pressure and bypass configuration must also match; the table above tags every equivalent as full, partial or verify for exactly this reason.

Same-envelope elements from other brands

View full interchange →

These 7 catalog element(s) share the 64×139 mm envelope. Envelope match alone does not guarantee interchangeability — compare micron/Beta, seals and collapse rating.

FS121B5T125B Filtrec · 125 µm FS121B5T60 Filtrec · 60 µm FS121B5T60B Filtrec · 60 µm FS121N5T125 Filtrec · 125 µm FS121N5T125B Filtrec · 125 µm FS121N5T250 Filtrec · 250 µm FS121N5T250B Filtrec · 250 µm

Other models in the Filtrec elements series

All 9874 (list page 8/20) →

A105C05 96×60 mm · 5 µm A105C10 96×60 mm · 10 µm A105C25 96×60 mm · 25 µm A105G03 96×60 mm · 5 µm A105G06 96×60 mm · 7 µm A105G10 96×60 mm · 12 µm A105G25 96×60 mm · 22 µm A105T125 96×60 mm · 125 µm A105T250 96×60 mm · 250 µm A105T60 96×60 mm · 60 µm

Reviewed & verified by the ElementRef engineering desk against Filtrec S.p.A. on 2026-10-03. Read our editorial & correction policy.