The AirTAC GFR300-08 AirTAC Filter Regulator NPT1/4 5 um Low-Pressure is a genuine G-series filter regulator: water separation, 5 µm particulate filtration and balanced-type pressure regulation combined in a single body. It has PT1/4" ports, a manual drain and regulates 0.05 - 0.9 MPa (7 - 130 psi). It does not lubricate — add a GL lubricator, or order the GFC two-unit set, if downstream equipment needs oil.
The AirTAC GFR300-08 is a filter regulator: it removes water and particulate from compressed air and regulates downstream pressure in a single body. This 300-size unit is fitted with a 1/4 in NPT port, a manual drain bowl in polycarbonate, and a fine 5 um filter element (code W) for applications that need cleaner air than the standard 40 um grade. It is the low-pressure type (code L) for circuits running at reduced supply pressure, and the F3 gauge code gives you the embedded square gauge with a bar scale. A reverse/check valve (code K) is fitted, and the mounting bracket is included.
This is a genuine AirTAC part from the GFR range, which spans sizes 200, 300, 400 and 600 with port sizes from 1/8 in to 1 in, a choice of differential-pressure, automatic or manual drains, 40 um or 5 um filtration, gauge scales in MPa, psi or bar, and PT, G or NPT threads. Flow is published as curves rather than a single rating, so ask us to confirm the flow or any datasheet figure for your application before ordering.
| Model | GFR300-08 AirTAC Filter Regulator NPT1/4 5 um Low-Pressure |
|---|---|
| Series | GFR300 filter regulator |
| Port size | PT1/4" (NPT thread) |
| Filtering grade | 5 µm |
| Regulating range | 0.05 - 0.9 MPa (7 - 130 psi) |
| Pressure type | Low-pressure type |
| Adjusting mechanism | Balanced type |
| Fluid | Compressed air |
|---|---|
| Max. working pressure | 1.0 MPa (145 psi) |
| Temperature range | -5 to +70 °C (unfreeze) |
| Drain type | Manual drain |
| Bowl material | PC |
| Pressure gauge | Fitted — square, bar scale |
| Reflux valve | Fitted (reverse flow permitted) |
Specifications follow the official AirTAC G-series air-preparation data. The regulating band is set by the drain type: automatic and differential-pressure drains regulate 0.15 - 0.9 MPa, a manual drain regulates 0.05 - 0.9 MPa. The low-pressure type adjusts over a lower band than standard; we confirm the exact figures from the factory datasheet. Air must not freeze in the unit. Flow curves, weight and outline dimensions are not published in our data set — ask us and we will confirm from the factory datasheet.
| GFR300 | G-series filter regulator, 300 body — sets the port range. |
|---|---|
| 08 | Port size PT1/4". This body offers 08 = PT1/4", 10 = PT3/8", 15 = PT1/2". |
| M | Drain: Manual drain — this also sets the regulating band (0.05 - 0.9 MPa (7 - 130 psi)). |
| L | Low-pressure type. Blank is standard, L is the low-pressure type. |
| (blank) | Mounting bracket included. |
| (blank) | Pressure gauge fitted (blank). |
| F | Gauge shape: Square. C is round, F is square. |
| 3 | Gauge scale: bar. 1 is MPa, 2 is psi, 3 is bar. |
| W | Filtering grade 5 µm. Only 40 µm (blank) and 5 µm (W) exist. |
| T | NPT thread. PT is the default; G is BSPP and T is NPT. |
| K | Reverse-flow (reflux) valve fitted. |
Field order is size, port, drain, type, bracket, gauge, shape, scale, grade, thread, reflux — a blank position takes the default. Example: GFR300-08 is a 300 body, PT1/4", differential drain, standard type, bracket included, gauge fitted, 40 µm, PT thread, no reflux valve.
A larger body carries a larger port and holds set pressure better as flow rises. AirTAC publishes flow only as curves, so size the body from your peak demand with headroom. The GFR600 uses an aluminium-alloy bowl; the 200, 300 and 400 bodies use PC.
| This model | GFR300 · PT1/4" · 5 µm |
|---|---|
| One size down | GFR200 |
| One size up | GFR400 |
| Add lubrication | GFC300-08 (two-unit set) |
Fixture clamps and swing cylinders on an assembly bench often run at reduced supply pressure. This low-pressure type filter regulator cleans the shop air to 5 um and holds the reduced setting, with the bar-scale gauge letting operators verify the clamp circuit at a glance.
Baggers, carton sealers and case packers use short-stroke air cylinders that are sensitive to water and fine contamination. A 5 um element with manual drain ahead of the machine's directional valves keeps the actuation air clean, and the check valve holds the set circuit if upstream supply dips.
Bench-top test rigs, air bearings and analytical instruments need clean, regulated air at modest pressures. Tapping a 1/4 in NPT line through this unit gives a fine 5 um supply with local bar-gauge readout, and the included bracket lets it mount directly to the rig frame.
Start with the port step: this unit is 300 size with a 1/4 in NPT thread; step up to 400 or 600 if your line needs more flow capacity, or down to 200 for compact circuits. The manual drain (code M) means someone opens the bowl drain during checks - choose automatic or differential-pressure drain if the unit sits where regular blowdown is impractical. The 5 um element (code W) suits air tools, valves and instruments that need finer filtration than the standard 40 um grade. The square gauge here reads in bar; MPa and psi scales are also available, and an external round gauge is an option. PT is the standard thread; G and NPT are order options. A bracket is included on this unit.
Flow for this family is published as curves, not a single rated figure, so we cannot quote one number here. Send us your application details and we will confirm sizing against the datasheet curves before you order.
Quick checklist
The PC bowl must not be cleaned with solvents — wipe it with a dry cloth. The reflux valve permits reverse flow through the unit. A filter regulator adds no oil to the line.
AirTAC publishes flow for the GFR series as curves rather than a single rated figure, so we do not quote one number. Tell us your line pressure, set pressure and expected air demand, and we will confirm the flow from the datasheet curves for this exact configuration before you order.
The M code in GFR30008MLF3WTK means the bowl drain is opened by hand during maintenance checks. If the unit is mounted in a hard-to-reach spot or on a line that runs unattended, ask for the automatic (A) or differential-pressure (blank) drain version instead - the rest of the specification stays the same.
Genuine AirTAC parts produced by AirTAC factory.
Covers non-human-caused product damage.
Standard models usually ship in 3-4 days.
Most inquiries answered within 7-8 hours.
Send us the quantity, thread type (PT / G / NPT), gauge scale and destination. We confirm price, availability and lead time — usually within 7-8 hours.