The AirTAC GFR300-08 AirTAC Filter Regulator G1/4, psi Gauge 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 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 has a G1/4 (BSPP) port, the standard 40 um filter element, a differential-pressure drain that bleeds collected condensate automatically as flow passes through, and a square pressure gauge reading in psi. A reverse/check valve is fitted, and the regulator covers an adjustment range of 0.15-0.9 MPa (20-130 psi). Maximum inlet pressure is 1.0 MPa (145 psi), and the operating temperature range is -5 to 70 C (non-freezing). The polycarbonate bowl keeps the fluid level and drain visible; only size-600 units in this series use an aluminium alloy bowl.
This is a genuine AirTAC part. The GFR series is available in sizes 200, 300, 400 and 600 with port sizes from 1/8 to 1 inch, a choice of 40 um or 5 um (code W) filtration, differential-pressure, automatic or manual drains, and G (BSPP) or NPT threads as order options alongside the PT standard. Flow figures for this series are published as curves rather than a single rated number, so ask us to confirm the datasheet and sizing for your application on request.
| Model | GFR300-08 AirTAC Filter Regulator G1/4, psi Gauge |
|---|---|
| Series | GFR300 filter regulator |
| Port size | PT1/4" (G (BSPP) 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 | Differential-pressure 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". |
| (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. |
| (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. |
| G | G (BSPP) 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 clamping cylinders on an assembly fixture: the GFR300-08 cleans the shop air of water and scale, then holds a set clamping pressure read directly on the psi gauge, while the check valve keeps the circuit from dumping if the main supply drops.
Supplying solenoid valve manifolds on a cartoning or wrapping line, where the 40 um element protects spool tolerances and the regulator sets the actuation pressure for sealing jaws and product pushers at a stable, repeatable level.
A point-of-use station on a 1/4 inch drop feeding impact drivers, grinders or air screwdrivers: the unit strips condensate carried from the main line, lets each operator dial in tool pressure on the psi gauge, and the differential-pressure drain keeps the bowl clear without daily manual bleeding.
Size 300 with a G1/4 port sits in the middle of the GFR range: step up to size 400 or 600, or down to size 200, as your line's flow demand dictates - we can confirm the flow curves against your consumption before you order. This unit keeps the standard 40 um element, which suits general-purpose actuation and air-tool supply; choose the 5 um (W) option only where finer particulate removal is required. The differential-pressure drain is the default and needs no operator attention; specify automatic (A) or manual (M) drain if your maintenance routine calls for it. The fitted square gauge reads in psi; round external gauges and MPa or bar scales are available alternatives. The reverse/check valve (K) holds downstream pressure if the upstream supply is lost. G thread is this unit's specification; PT is the series standard and NPT can be ordered. A mounting bracket is not included with this code (J).
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 rated flow number we can honestly quote. Tell us your application and consumption and we will confirm the flow curve and correct sizing from the datasheet on request before you order.
K indicates a reverse/check valve is fitted. If upstream pressure is lost, the valve holds the regulated downstream pressure instead of venting it - useful on clamp or hold circuits where losing pressure mid-cycle would release a workpiece. If you do not want this function, the same unit is available without the check valve.
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.