The AirTAC GFR300-08 AirTAC Filter Regulator NPT1/4 Auto Drain is a genuine G-series filter regulator: water separation, 40 µm particulate filtration and balanced-type pressure regulation combined in a single body. It has PT1/4" ports, a automatic 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 holds downstream pressure steady in a single body. This configuration is built with a 1/4 in NPT port, an automatic drain that expels collected condensate on its own, a 40 um filter element, an embedded square gauge reading in psi, and a reverse/check valve fitted. Maximum inlet pressure is 1.0 MPa (145 psi), the regulating range is 0.15-0.9 MPa (20-130 psi), and the operating temperature is -5 to 70 C (non-freezing). The polycarbonate bowl is the standard material at this size.
This is a genuine AirTAC part. The GFR300 is one size in the GFR line, which spans 200/300/400/600 sizes, ports from 1/8 to 1 in, PT, G and NPT threads, differential-pressure, automatic or manual drains, 40 um standard or 5 um (W) elements, and gauge scales in MPa, psi or bar. Flow is published as curves rather than a single rating, so ask us and we will confirm the datasheet figures for your application on request.
| Model | GFR300-08 AirTAC Filter Regulator NPT1/4 Auto Drain |
|---|---|
| Series | GFR300 filter regulator |
| Port size | PT1/4" (NPT thread) |
| Filtering grade | 40 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 | Automatic drain |
| Bowl material | PC |
| Pressure gauge | Fitted — square, 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. 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". |
| A | Drain: Automatic 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. |
| (blank) | Pressure gauge fitted (blank). |
| F | Gauge shape: Square. C is round, F is square. |
| 2 | Gauge scale: psi. 1 is MPa, 2 is psi, 3 is bar. |
| (blank) | Filtering grade 40 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" · 40 µm |
|---|---|
| One size down | GFR200 |
| One size up | GFR400 |
| Add lubrication | GFC300-08 (two-unit set) |
Feeding filtered, regulated air to the solenoid valves and pneumatic clamps on a machining centre: the 40 um element keeps condensate and pipe scale out of the valve seats while the set pressure holds workholding fixtures consistent.
Regulating air to carton-sealing and diverting cylinders on a packaging conveyor, where the automatic drain clears condensate by itself across multi-shift runs and the check valve holds the downstream setting if supply dips.
A paint or coating booth drop where steady pressure at the gun matters: the regulator holds the atomising setpoint and the 40 um element catches water and debris before they reach the finish.
Choose the size by the port and the flow your line needs: GFR300 with its 1/4 in NPT port is the usual step for point-of-use drops feeding cylinders, valves or spray guns. Pick the drain to match attendance: automatic (this unit) drains itself, manual needs a routine bleed, and the differential-pressure default discharges on a pressure drop. The 40 um element is the standard grade; specify W for 5 um where finer filtration is wanted. The embedded square gauge here reads psi, with MPa and bar scales and an external round gauge as options. PT is the standard thread and G or NPT are order options; a bracket can be added, though this unit is specified without one. 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 GFR300 as curves rather than a single rated figure, so we do not quote a number here. Send us your application conditions and we will confirm the datasheet flow for this 1/4 in port unit on request.
The automatic drain expels collected condensate from the bowl without anyone opening it, which suits unattended or multi-shift installations. The GFR family is also available with a manual drain for routinely attended points, or the differential-pressure drain (the default code) that discharges on a pressure drop.
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.