The AirTAC GFR300-08 AirTAC Filter Regulator 1/4 in NPT Low-Pressure 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 manual drain and regulates 0.05 - 0.9 MPa (7 - 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 sets downstream pressure in one body. This configuration is the low-pressure type, so it suits circuits that must run well below standard working pressure. It has a 1/4 in NPT port, a manual drain bowl in polycarbonate, a 40 um standard filter element, a round pressure gauge with MPa scale, and no mounting bracket or reverse/check valve. Maximum inlet pressure is 1.0 MPa (145 psi) and the working temperature range is -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 port sizes from 1/8 in to 1 in, a choice of PT, G or NPT thread, manual, automatic or differential-pressure drains, a 5 um element option, gauge styles and scales, and a bracket option. Flow is published as curves rather than a single rated figure, so ask us to confirm the datasheet and sizing for your application.
| Model | GFR300-08 AirTAC Filter Regulator 1/4 in NPT Low-Pressure |
|---|---|
| Series | GFR300 filter regulator |
| Port size | PT1/4" (NPT thread) |
| Filtering grade | 40 µm |
| Regulating range | 0.05 - 0.9 MPa (7 - 130 psi) |
| Pressure type | Low-pressure 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 | Manual drain |
| Bowl material | PC |
| Pressure gauge | Fitted — round, MPa 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. The low-pressure type adjusts over a lower band than standard; we confirm the exact figures from the factory datasheet. 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". |
| M | Drain: Manual drain — this also sets the regulating band (0.05 - 0.9 MPa (7 - 130 psi)). |
| L | Low-pressure 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. |
| (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" · 40 µm |
|---|---|
| One size down | GFR200 |
| One size up | GFR400 |
| Add lubrication | GFC300-08 (two-unit set) |
Filtered, low-pressure air to clamp cylinders and swing clamps on a CNC fixture, where the workpiece requires a gentler holding pressure than the shop main line provides.
Conditioned air for grippers, pushers and diverters on a filling or bottling line, with the manual drain bled at shift start-up to keep condensate out of the actuators.
Regulated supply to delicate packaging heads and small air cylinders that are rated well below standard line pressure, with the 40 um element protecting seals and valves from grit and water.
Start with the port step: size 300 with a 1/4 in NPT port sits in the middle of the GFR range, and larger sizes carry larger ports and more flow. Choose the drain to match maintenance access: this unit has a manual drain, which needs periodic bleeding, while automatic and differential-pressure drains handle condensate without operator action. The 40 um element fitted here is the standard grade; specify code W for the 5 um option where finer filtration is needed. The round MPa-scale gauge is fitted on this configuration, and embedded square gauges with MPa, psi or bar scales are available. Thread is NPT here; PT is the standard and G is also an order option. A bracket can be added where this one is omitted.
Because flow is published as curves rather than a single rating, ask us to confirm sizing against your air demand before ordering. The exact regulation range of the low-pressure type is also confirmed on request.
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 rather than a single rated figure, so we do not quote one number. Tell us your air demand and line conditions and we will confirm the sizing from the datasheet on request.
The M in the code means the polycarbonate bowl is drained by hand, so an operator bleeds accumulated condensate periodically instead of relying on an automatic or differential-pressure drain. The L marks the low-pressure regulator type, intended for circuits that run well below standard working pressure; its exact regulation range is confirmed on request.
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.