Airtac MFJ Adjustable Mini Cylinder MFJ25X125-40S
The AirTAC Airtac MFJ Adjustable Mini Cylinder MFJ25X125-40S is a genuine double acting, adjustable stroke JIS-standard round-body mini air cylinder with a Ø25mm bore and 125mm stroke, 1/8" air ports and a SUS304 stainless-steel barrel for mildly corrosive environments. For the same bore and stroke it is shorter than an ISO 6432 cylinder, saving mounting space.
- BoreØ25 mm
- Stroke125 mm
- Port size1/8"
- Acting typeDouble acting, adjustable stroke
- Rod threadM10×1.25
- CushionFixed TPU bumper pads
- No minimum order. A single piece can be ordered.
- Ready in 3–5 business days. That is the time we take to process the order and hand it to the carrier. Transit time after that depends on the destination.
About the Airtac MFJ Adjustable Mini Cylinder MFJ25X125-40S
Trimming the extend stroke by up to 40 mm directly on the machine, this JIS-standard round-body mini cylinder lets you set a precise 85 to 125 mm end position without buying a new unit. The SUS304 stainless barrel and riveted aluminium covers form a compact body that is physically shorter than an ISO 6432 cylinder of the same bore and stroke, saving valuable mounting length while resisting mild washdown.
Driven by filtered air at 0.15 to 1.0 MPa through a 1/8" port, the Ø10 mm rod delivers 245.3 N of push force at 0.5 MPa. Because this SKU includes the -S magnet, it is fully ready for CMSG, DMSG or EMSG position sensing. The fixed TPU bumper pads absorb end-of-stroke impacts across the 30 to 800 mm/s speed range.
Airtac MFJ Adjustable Mini Cylinder MFJ25X125-40S Technical Specifications
| Model | Airtac MFJ Adjustable Mini Cylinder MFJ25X125-40S |
|---|---|
| Series | MFJ JIS mini cylinder |
| Bore size | Ø25 mm |
| Stroke | 125 mm |
| Acting type | Double acting, adjustable stroke |
| Port size | 1/8" |
| Rod thread | M10×1.25 |
| Fluid | Air (filtered by 40µm element) |
|---|---|
| Operating pressure | 0.15 – 1.0 MPa |
| Proof pressure | 1.5 MPa |
| Temperature | -20 to +70 °C |
| Speed range | 30 – 800 mm/s |
| Cushion | Fixed TPU bumper pads |
| Max standard stroke | Up to 500 mm |
Specifications follow the official AirTAC MF/MFC (JIS-standard) datasheet. Barrel: SUS304 stainless steel; covers: aluminum alloy (round-body, riveted rolling-packed construction). Thread options: PT (blank) / G / NPT.
Theoretical Output Force (Ø25mm)
| Pressure | Push force | Pull force |
|---|---|---|
| 0.5 MPa | 245 N | 206 N |
| 0.7 MPa | 344 N | 289 N |
| Max (@1.0 MPa) | 50 kgf | |
Actual usable force is lower than theoretical due to friction and back-pressure. Size with a safety margin.
Model Code: Airtac MFJ Adjustable Mini Cylinder MFJ25X125-40S
| MFJ | JIS-standard round-body mini cylinder (adjustable-stroke). |
|---|---|
| 25 | Bore size in mm. |
| ×125 | Stroke length in mm. |
| -S | Optional built-in magnet for CMSG / DMSG / EMSG sensors. |
MF-family variants: MF / MFC (double acting ±cushion), MSF / MTF (single acting push / pull), MFD / MFCD (double rod ±cushion), MFJ / MFCJ (adjustable stroke ±cushion). Back covers CA / U / CM. Mounting LB / FA / SDB / TC.
Where the Airtac MFJ Adjustable Mini Cylinder MFJ25X125-40S Is Used
Changeover Dial-In
Fine-tune the extend end within the 40 mm window during product format changes, using the 245.3 N push force to seat varying fixtures without swapping cylinders.
Trial-Fit Rigs
Dial in the exact 85 to 125 mm extend position on prototype assembly stations, leveraging the 12.5 kg vertical lift capacity to test part placement before finalizing stops.
Variable-Position Stops
Adjust the external rod stop on the fly for flexible clamping tasks, letting the fixed TPU bumper absorb the impact while the -S magnet confirms end position.
Is the Airtac MFJ Adjustable Mini Cylinder MFJ25X125-40S the Right Cylinder?
When sizing these adjustable-stroke units, compare the actual outputs: the MFJ20 provides 157 N of push at 0.5 MPa, this MFJ25 hits 245.3 N, and the larger MFJ32 offers 402.2 N. Choose the 25 mm bore when your trial-fit or changeover rig needs a safe working load around 147 N, which equates to lifting roughly 12.5 kg vertically with a 2:1 margin. The external adjuster is ideal for dialing in an unknown final position during commissioning, but remember it only shortens the extend stroke and does not act as a mid-stroke lock.
For mounting, select from LB foot, FA flange or TC trunnion brackets (there is no SDB or back-cover option on this build). If your application must hold a load vertically during an air loss event, the piston will drift; add an external rod lock or pilot-operated check valve rather than relying on the bumper. The built-in -S magnet pairs directly with CMSG, DMSG or EMSG switches for electronic or reed feedback.
Quick checklist
- ✓ Required force at your working pressure
- ✓ Stroke and mounting space
- ✓ Port/thread type (PT / G / NPT)
- ✓ Magnet (-S) for sensors?
- ✓ Back cover (CA/U/CM) & mount (LB/FA/SDB/TC)
Installation & Maintenance Notes
- check Use clean air filtered to 40µm or finer.
- check Keep within 0.15 – 1.0 MPa operating pressure.
- check Avoid side load on the piston rod.
- check Do not dismantle the riveted front/back covers.
- check Use correct back cover (CA/U/CM) & mount (LB/FA/SDB/TC).
- check Installation by qualified personnel per AirTAC docs.
Airtac MFJ Adjustable Mini Cylinder MFJ25X125-40S FAQ
This 25 mm bore cylinder uses a 1/8" air port and a Ø10 mm rod. It generates 245.3 N push and 206.1 N pull at 0.5 MPa, 343.4 N push and 288.5 N pull at 0.7 MPa, with a theoretical maximum of 50 kgf at 1.0 MPa.
An external adjuster shortens the extend stroke by up to 40 mm on-site, giving a usable 85 to 125 mm extend window while retract remains full. It uses fixed TPU bumper pads to decelerate the stroke end, not an adjustable air cushion. The included -S magnet enables CMSG, DMSG and EMSG sensors.
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Genuine AirTAC parts produced by AirTAC factory.
1-Year Warranty
Covers non-human-caused product damage.
Fast Dispatch
Standard models are processed and dispatched in 3-5 business days.
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Most inquiries answered within 7-8 hours.
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