The AirTAC AirTAC GFR300-08 Filter Regulator 1/4 in NPT, 5 um 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 built with a 1/4 in NPT port, an automatic drain that expels collected condensate without manual attention, a fine 5 um filter element for cleaner air than the standard 40 um grade, and a round pressure gauge reading in bar. The standard regulator covers an adjustment range of 0.15-0.9 MPa (20-130 psi), with a maximum inlet pressure of 1.0 MPa (145 psi), and the polycarbonate bowl suits operating temperatures of -5 to 70 C (non-freezing).
This is a genuine AirTAC part. The GFR family is available in sizes 200, 300, 400 and 600 with ports from 1/8 in to 1 in, and with choices of drain type, filter grade, gauge style and scale, thread (PT standard, G and NPT as options) and bracket. Flow figures are published as curves rather than a single rating, so ask us to confirm the datasheet figures for your application before ordering.
| Model | AirTAC GFR300-08 Filter Regulator 1/4 in NPT, 5 um |
|---|---|
| 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 | Fitted — round, bar scale |
| Reflux valve | Not fitted |
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). |
| C | Gauge shape: Round. C is round, F is square. |
| 3 | Gauge scale: bar. 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. |
| (blank) | No reverse-flow valve (the default). |
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) |
Clean, regulated air for a bench-mounted pneumatic press or clamping fixture, where the 5 um element protects directional valves and cylinders from particulate and the automatic drain keeps condensate off the shop floor.
Point-of-use conditioning on a cartoning or wrapping line, giving machine-mounted actuators a stable set pressure read locally on the bar gauge while the automatic drain handles moisture through continuous shifts.
Regulated supply to pneumatic control panels and positioners in a process plant, where the fine 5 um grade and a confirmed set point in bar keep pilot-operated components working reliably.
Size 300 with a 1/4 in port is a mid-range step in the GFR line; step up to 400/600 or down to 200 according to the flow your line needs. The automatic drain on this unit suits unattended duty; choose manual or differential-pressure drain if you prefer controlled or load-proportional purging. The 5 um element (code W) is the finer option over the standard 40 um grade and is worth specifying for sensitive downstream valves and instruments. The round gauge reads in bar; square embedded gauges and MPa or psi scales are also available. PT is the standard thread, with G (BSPP) and NPT as order options, and brackets can be added or omitted.
Because flow is published as curves rather than a single rated figure, we do not quote a number here. Send us your application details and we will confirm the sizing against the datasheet curves before you order.
Quick checklist
The PC bowl must not be cleaned with solvents — wipe it with a dry cloth. Without the K option, air cannot flow back 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 here. Tell us your application and we will confirm the datasheet flow curve for the GFR300 size so you can check it against your required flow before ordering.
This configuration carries the A drain code, meaning an automatic drain that expels collected condensate on its own - useful where the unit is mounted in a hard-to-reach spot or runs unattended. If you prefer to purge manually or want a differential-pressure drain, the same GFR300-08 body is available with M (manual) or the default differential-pressure drain; just ask for that variant.
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.