The AirTAC GFR300-08 AirTAC Filter Regulator NPT1/4 5um 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 size-300 filter regulator that removes water and particulate from compressed air and regulates downstream pressure in one body. This configuration is threaded NPT1/4 (1/4 in), carries the fine 5 um filter element (W), drains condensate by the differential-pressure method, and includes a reverse/check valve that holds downstream pressure when the supply is interrupted. No gauge is fitted (code N) and no mounting bracket is supplied (code J). The polycarbonate bowl suits the 200/300/400 sizes, maximum inlet pressure is 1.0 MPa (145 psi), the standard regulator covers 0.15-0.9 MPa (20-130 psi), and the operating temperature range is -5 to 70 C (non-freezing).
This is a genuine AirTAC part. The GFR family spans sizes 200, 300, 400 and 600 with port sizes from 1/8 in to 1 in, a choice of 40 um standard or 5 um (W) filtration, differential-pressure, automatic or manual drains, gauge and scale options, and PT, G or NPT threads. We confirm flow and datasheet figures on request, since flow is published as curves rather than a single rating.
| Model | GFR300-08 AirTAC Filter Regulator NPT1/4 5um |
|---|---|
| Series | GFR300 filter regulator |
| Port size | PT1/4" (NPT thread) |
| Filtering grade | 5 µm |
| Regulating range | 0.15 - 0.9 MPa (20 - 130 psi) |
| Pressure type | Standard 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 | Not fitted |
| 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. Standard type, regulating 0.15 - 0.9 MPa (20 - 130 psi). 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)). |
| (blank) | Standard type. Blank is standard, L is the low-pressure type. |
| J | Supplied without bracket. |
| N | No pressure gauge (N). |
| (blank) | Gauge shape: Factory standard. C is round, F is square. |
| (blank) | Gauge scale: Factory standard. 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) |
Feeding a clamping cylinder circuit on a fabrication press: the 5 um element keeps solenoid valves clean while the regulator holds the clamp pressure the tooling was set up for, and the check valve holds the circuit if the supply drops.
Supplying air to stoppers, pushers and diverters along a packaging conveyor, where the 1/4 in port matches typical cylinder circuit tubing and the differential-pressure drain clears condensate during continuous shifts.
Conditioning the air feed to bench-top lab and test instruments that need fine filtration and a stable set pressure, with the 5 um element protecting sensitive pneumatic controls downstream.
Size 300 with a 1/4 in port sits mid-range in the GFR line; step up to 400 or 600, or down to 200, according to the flow your line needs. This unit already carries the 5 um (W) element - choose 40 um where general protection is enough and 5 um where downstream valves and instruments need finer air. The differential-pressure drain is the default and suits steady operation; automatic or manual drains are available in other codes. A gauge can be added in other variants (square embedded or external round, in MPa, psi or bar scales), and PT, G or NPT threads are order options - this code is NPT. No bracket is included in this code; bracketed versions exist. Flow is published as curves, not a single rating, so ask us to confirm sizing against your application before ordering.
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, not as a single rated figure, so we do not quote a number. Send us your application details and we will confirm the flow and sizing from the datasheet on request before you order.
The code GFR30008JNWTK carries the N gauge position, so no pressure gauge is fitted. Other GFR300-08 variants include an embedded square gauge or an external round gauge with MPa, psi or bar scales - ask us for the right code if you want a gauge.
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.