The AirTAC AirTAC GFR300-08 Filter Regulator 1/4 in NPT, 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: one body that removes water and particulate from compressed air and sets downstream pressure, so a single 1/4 in ported unit does both jobs. This configuration has an automatic drain that ejects collected condensate without manual attention, a 40 um standard filter element, an embedded square gauge reading in bar, and a reverse/check valve that holds downstream pressure when the supply is lost. It is supplied without a mounting bracket. Maximum inlet pressure is 1.0 MPa (145 psi), the standard regulator adjusts from 0.15-0.9 MPa (20-130 psi), and the operating temperature range is -5 to 70 C (non-freezing). The polycarbonate bowl suits the 300 size; only the 600 size uses an aluminium alloy bowl.
This is a genuine AirTAC part in the GFR300 series, one of four sizes (200, 300, 400, 600) that step up in port size and flow capacity, with port options in PT, G (BSPP) and NPT. Flow for this series is published as curves rather than a single rated figure, so ask us to confirm the datasheet and sizing for your application before ordering.
| Model | AirTAC GFR300-08 Filter Regulator 1/4 in NPT, 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, 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. 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. |
| 3 | Gauge scale: bar. 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 a bench-mounted pneumatic press or clamping fixture from a shop-air drop, where the regulator sets a stable working pressure and the automatic drain keeps condensate out of the cylinder valves.
Supplying the air cylinders that drive gates, pushers and stops on a packaging conveyor, with the 40 um element protecting directional valves from water and pipe scale and the check valve holding position during an air outage.
Regulating clean, dry air to actuators and grippers on an automated laboratory or test-rig setup, where the bar-scale square gauge gives a clear local setpoint readout and the automatic drain suits unattended overnight runs.
Choose the size by port and required flow: the GFR300 with its 1/4 in port suits compact supply drops, while 200, 400 and 600 sizes cover smaller and larger lines. Drain is a real choice here: automatic (this unit) for unattended duty, manual where you prefer operator-controlled draining, or the differential-pressure default. Filter grade is 40 um standard or 5 um (code W) where finer particulate protection is needed. The embedded square gauge is standard; an external round gauge is optional, with MPa, psi or bar scales. Thread is PT as standard, with G (BSPP) and NPT as orderable options - this unit is the NPT version. Brackets are optional on this family.
One honest note on sizing: flow for the GFR series is published as curves, not a single rating, so send us your application details and we will confirm the right size against the datasheet 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 there is no one number we can honestly quote. Tell us your line pressure, set pressure and the equipment you are feeding, and we will confirm the sizing against the datasheet for you before you order.
The A in the code sets automatic draining: collected condensate is ejected from the polycarbonate bowl without anyone opening a valve, which suits unattended or hard-to-reach installations. The K adds a reverse/check valve, so downstream pressure is held if the upstream supply drops. Manual-drain and differential-pressure-drain versions, and units without the check valve, are available in the same series.
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.