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 size-300 filter regulator that removes water and particulate from compressed air and regulates downstream pressure in one body. This configuration has a 1/4 in NPT port, an automatic drain that ejects collected condensate without manual attention, a 40 um standard filtration element, a fitted reverse/check valve that holds the downstream setting when upstream pressure is lost, and an external round pressure gauge scaled in MPa. Maximum inlet pressure is 1.0 MPa (145 psi), the standard regulation range is 0.15-0.9 MPa (20-130 psi), and the operating temperature range is -5 to 70 C (non-freezing). The polycarbonate bowl lets you see the condensate level at a glance.
This is a genuine AirTAC part. The GFR family is offered in sizes 200, 300, 400 and 600 with port sizes from 1/8 in to 1 in, and with choices of drain type, 40 um or 5 um filtration, gauge style and scale, thread (PT standard, G and NPT as order options) and bracket. Flow is published as curves rather than a single rating, so ask us to confirm the datasheet figures for your application before ordering.
| 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 — round, MPa 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). |
| C | Gauge shape: Round. C is round, F is square. |
| 1 | Gauge scale: MPa. 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) |
Point-of-use conditioning for the air feeding a machining centre's tool changer and clamping circuits: water and chips of contamination are stripped out at 40 um and the regulated pressure holds the clamp force steady, with the check valve keeping the setting through upstream dips.
Conditioning the air to pneumatic cylinders on a carton-forming and sealing conveyor: the automatic drain copes with condensate on a line that runs unattended across shifts, and the regulator keeps cylinder speed consistent for repeatable seal positioning.
A filter regulator at the wall drop feeding hand-held pneumatic tools and small actuators in an assembly cell: the round MPa gauge gives operators a visible setpoint, and the 1/4 in port matches standard drop hoses and fittings.
Size 300 with a 1/4 in NPT port suits lines where the required flow sits within the mid range of the GFR family; step up to size 400 or 600, or down to size 200, according to the flow curve for your consumption. The automatic drain on this unit is the right choice when the bowl is mounted where regular manual draining is impractical; a manual-drain variant widens the regulation range down to 0.05 MPa if you need very low setpoints. The 40 um element is the standard grade for general plant air; specify the W code for 5 um when downstream equipment needs finer filtration. The fitted round gauge reads in MPa; psi and bar scales are available. NPT is the thread on this unit; PT is the catalogue standard and G (BSPP) is also orderable. A mounting bracket is not included with the J code on this unit - add one if you want the unit secured independent of the piping. Because flow is published as curves and not as a single rated figure, send us your application details and we will confirm sizing 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, not as a single rated figure, so we do not quote a number here. Tell us your operating pressure and air consumption and we will confirm the flow from the datasheet for this exact unit before you order.
The A code means the bowl drains itself: collected condensate is discharged automatically, so the unit suits installations that are not checked daily. The K code means a reverse/check valve is fitted, which holds the downstream pressure setting if the upstream supply is interrupted. If you prefer manual draining or need setpoints down to 0.05 MPa, ask about the manual-drain 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.