The AirTAC AirTAC GFR300-08 Filter Regulator G1/4 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 differential-pressure drain and regulates 0.15 - 0.9 MPa (20 - 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 G1/4 (BSPP) port, a 5 um filter element (the finer of the two published grades), a differential-pressure drain that bleeds collected condensate automatically whenever the pressure differential across the bowl is high enough, and a reverse/check valve that holds downstream pressure when the upstream supply is lost. It is the low-pressure (L) type, intended for circuits that need a reduced outlet pressure, and it carries a round pressure gauge reading in psi. The polycarbonate bowl is protected by a metal guard, and the mounting bracket is included.
This is a genuine AirTAC part from the GFR series, which spans sizes 200, 300, 400 and 600 with ports from 1/8 to 1 inch, a choice of differential-pressure, automatic or manual drains, 40 um or 5 um elements, standard or low-pressure regulation, and PT, G or NPT threads. Maximum working (inlet) pressure is 1.0 MPa (145 psi) and the operating temperature range is -5 to 70 C, non-freezing. AirTAC publishes flow for this series as curves rather than a single rated figure, so ask us to confirm flow and any other datasheet figure for your application before ordering.
| Model | AirTAC GFR300-08 Filter Regulator G1/4 5 um Low-Pressure |
|---|---|
| Series | GFR300 filter regulator |
| Port size | PT1/4" (G (BSPP) thread) |
| Filtering grade | 5 µm |
| Regulating range | 0.15 - 0.9 MPa (20 - 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 | Differential-pressure drain |
| Bowl material | PC |
| Pressure gauge | Fitted — round, psi 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". |
| (blank) | Drain: Differential-pressure drain — this also sets the regulating band (0.15 - 0.9 MPa (20 - 130 psi)). |
| L | Low-pressure type. Blank is standard, L is the low-pressure type. |
| (blank) | Mounting bracket included. |
| (blank) | Pressure gauge fitted (blank). |
| C | Gauge shape: Round. C is round, F is square. |
| 2 | Gauge scale: psi. 1 is MPa, 2 is psi, 3 is bar. |
| W | Filtering grade 5 µm. Only 40 µm (blank) and 5 µm (W) exist. |
| G | G (BSPP) 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) |
Pneumatic clamps and swing cylinders on an assembly fixture often need a lower, tightly held supply pressure than the plant main. This low-pressure type filter regulator conditions the air, removes water and 5 um particles ahead of the valve stack, and its check valve holds the clamp circuit if the main supply drops.
Tool changers and pallet clamps on a compact machining centre need clean, dry air at a reduced, stable setting. Feeding the tool-change manifold through this G1/4 filter regulator keeps swarf-hostile moisture and fine particulate out of the directional valves, with the psi gauge giving the setter a local reading.
Diverter flaps, pushers and reject gates on a packaging conveyor run many short strokes per minute and suffer early from wet, dirty air. A filter regulator at the drop to each station removes condensate via the differential-pressure drain and sets the gentle pressure these actuators need, while the check valve prevents back-feed between stations.
Start with the port step: within the GFR series, size 300 with a 1/4 in port suits lines whose flow demand sits in the middle of the range, while sizes 200, 400 and 600 step up or down. Because flow is published as curves rather than one rated number, tell us your application and we will confirm sizing against the datasheet before you order. This unit is already configured with the 5 um element (the 40 um standard element is the alternative if your air quality is less critical), a differential-pressure drain (automatic and manual drains are the other catalogue choices), and the low-pressure regulator type where the standard type would not reach low enough outlet settings. The round gauge fitted here reads in psi; an embedded square gauge with MPa, psi or bar scales is the other option. Thread is G (BSPP) on this unit; PT is the standard thread and G or NPT are order options. A mounting bracket is included, and the reverse/check valve is fitted.
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 does not publish a single rated flow figure for the GFR series; flow is given only as curves in the catalogue. We will gladly pull the datasheet and confirm the flow curve for this 300-size, G1/4 unit against your application before you order - just ask.
The L code means the regulator is built for circuits that need a reduced outlet pressure, where the standard type would not adjust low enough. The exact adjustment range for the low-pressure variant is not published as a single figure, so we confirm it from the datasheet on request. Everything else on this unit - G1/4 port, 5 um element, differential-pressure drain, psi gauge, check valve and included bracket - is unchanged.
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.