The AirTAC GFR300-08 AirTAC Filter Regulator NPT1/4 5 um Auto Drain 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 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 size-300 filter regulator that removes water and particulate from compressed air and regulates downstream pressure in a single body. This configuration is fitted with a 5 um filter element (code W) for finer filtration than the standard 40 um grade, an automatic drain that expels collected condensate without manual attention, and a reverse/check valve that holds downstream pressure when the upstream supply is lost. The outlet pressure is adjustable over 0.15-0.9 MPa (20-130 psi), the maximum inlet pressure is 1.0 MPa (145 psi), and the operating temperature range is -5 to 70 C (non-freezing). No gauge is fitted on this variant and no mounting bracket is included.
This is a genuine AirTAC part in the GFR300 series, which covers 1/4 in ports in the G-series size range of 200, 300, 400 and 600 with PT, G or NPT thread options, a choice of drain types, 40 um or 5 um filtration, gauge options and bracket options. Flow is published in the AirTAC catalogue as curves rather than a single rated figure, so we confirm the datasheet and flow figures for your application on request.
| Model | GFR300-08 AirTAC Filter Regulator NPT1/4 5 um Auto Drain |
|---|---|
| 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 | Automatic 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". |
| 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. |
| 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 clamping cylinders and vise actuators on a machining centre, where the 5 um element protects the directional valves and the check valve holds clamp pressure if the shop air supply drops.
Conditioning air to vacuum generators and gripper cylinders on a carton or bottle packaging conveyor, with the automatic drain keeping condensate out of the circuit on a line that runs unattended across shifts.
Regulating supply pressure to air screwdrivers, presses and fixture cylinders at a bench assembly station, with the 5 um grade guarding the tools' internal valves against water and fine dirt.
Sizing a GFR filter regulator starts with the port step: this unit is 1/4 in NPT in the size-300 body, so match it to the line size and the flow your actuators actually draw - if the application sits near the top of the size-300 flow curve, step up to size 400 rather than oversizing the element. The 5 um element (code W) suits air prep ahead of sensitive valves and cylinders; the standard 40 um grade is the usual choice for general plant air. The automatic drain on this unit suits unattended or hard-to-reach installations; choose manual drain where you prefer controlled, scheduled draining, or differential-pressure drain as the catalogue default. A check valve is already fitted here, which is worth specifying whenever the downstream circuit must hold pressure through a supply loss. No gauge is fitted, so add a gauge separately if the setpoint needs visual verification. Thread is NPT on this variant (PT is the catalogue standard; G is also orderable), and no bracket is included - order one if the unit will be wall or panel mounted.
Because AirTAC publishes flow as curves rather than a single rated number, ask us to confirm sizing against your application and the full datasheet 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 series as curves rather than a single rated figure, so there is no one rated flow number we can honestly quote. Send us your inlet pressure and the air consumption of the equipment you are feeding, and we will confirm the flow and the full datasheet figures against your application before you order.
This variant carries the gauge code N, so no gauge is fitted as supplied - the regulator still adjusts over 0.15-0.9 MPa (20-130 psi) exactly as specified. If you want to read the setpoint at the unit, order a GFR300 variant with a gauge (square embedded or external round, in MPa, psi or bar scale), or fit a separate gauge downstream.
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.