The AirTAC GR300-08 AirTAC Air Pressure Regulator NPT1/4 Low-Pressure is a genuine G-series air pressure regulator. It holds a stable downstream pressure over the range 0.05 - 0.4 MPa (7 - 58 psi) with PT1/4" ports, and ships with a pressure gauge. A regulator does not filter the air — put a GF filter upstream, or use a GFR filter regulator, when water and particulate must also be removed.
The GR300-08 is a genuine AirTAC GR-series air pressure regulator: regulation only, with no filter, no bowl and no lubricator in the circuit. This unit is the low-pressure type (code L), so it regulates downstream pressure up to 0.4 MPa, with a maximum working (inlet) pressure of 1.0 MPa (145 psi). The 08 port code gives a 1/4 in NPT connection (PT is the standard thread for the series; G and NPT are order options). A square gauge with a psi scale is fitted as standard, an external round gauge is available, and the reverse/check valve (code K) is fitted to help hold downstream pressure. No mounting bracket is included on this configuration; the GR series is also panel-mountable. Operating temperature is -20 to 70 C, wider than the rest of the G family.
This is a genuine AirTAC part in the GR300 size, one of four sizes in the series (200 / 300 / 400 / 600) with a choice of port, thread, gauge scale, standard or low-pressure regulation, reverse valve and bracket. Flow for the GR series is published as curves rather than a single rated figure, so ask us to confirm the datasheet and flow figures for your application on request.
| Model | GR300-08 AirTAC Air Pressure Regulator NPT1/4 Low-Pressure |
|---|---|
| Series | GR300 pressure regulator |
| Port size | PT1/4" (NPT thread) |
| Regulating range | 0.05 - 0.4 MPa (7 - 58 psi) |
| Pressure type | Low-pressure type |
| Bracket | Supplied without bracket |
| Fluid | Compressed air |
|---|---|
| Max. working pressure | 1.0 MPa (145 psi) |
| Temperature range | -20 to +70 °C |
| Pressure gauge | Fitted — square, psi scale |
| Reflux valve | Fitted (reverse flow permitted) |
| Mounting | Panel mounting; optional fixing bracket |
Specifications follow the official AirTAC G-series air-preparation data. Note the GR temperature range is -20 to +70 °C, wider than the other G-series units. A regulator has no bowl and no filter element, so there is no filtering grade. Flow curves, weight and outline dimensions are not published in our data set — ask us and we will confirm from the factory datasheet.
| GR300 | G-series pressure regulator, 300 body — sets the port range. |
|---|---|
| 08 | Port size PT1/4". This body offers 08 = PT1/4", 10 = PT3/8", 15 = PT1/2". |
| L | Low-pressure type — 0.05 - 0.4 MPa (7 - 58 psi). 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. |
| 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, type, bracket, gauge, gauge shape, scale, thread, reflux — a blank position takes the default. Example: GR300-08LNK is a 300 body, PT1/4", low-pressure type, no gauge, with 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 rather than from a single rated figure.
| This model | GR300 · PT1/4" · 0.05 - 0.4 MPa (7 - 58 psi) |
|---|---|
| One size down | GR200 |
| One size up | GR400 |
| Line order | Filter first, then regulator, then lubricator |
Set a stable reduced pressure ahead of spray guns on a finishing line, where atomizing air must sit well below full line pressure and the psi gauge lets operators dial in the setting.
Feed low-pressure air to light-duty cylinders and actuators on a carton-sealing or wrapping conveyor, with the fitted check valve helping hold the set downstream pressure between strokes.
Regulate instrument-grade reduced pressure on a laboratory or pilot-plant bench where the process runs below 0.4 MPa and the -20 to 70 C range covers a temperature-controlled room.
Size 300 with a 1/4 in port is the mid-small step in the GR range; step up to 400 or 600, or down to 200, as your line's flow demand and piping change. Choose the low-pressure type (this unit, up to 0.4 MPa) when the process needs reduced pressure below the standard range's ceiling; the standard GR type regulates 0.05-0.9 MPa. The fitted square gauge reads in psi; MPa and bar scales are the other catalogue choices, and an external round gauge is optional. Thread: PT is the series standard, while G (BSPP) and NPT (this unit) are order options - specify the one that matches your piping. The fitted reverse/check valve (K) suits circuits where downstream pressure must be held; omit it if not needed. Bracket is not included on this code (J), and GR is also panel-mountable. Flow is published as curves, not a single rating, so ask us to confirm sizing against your application before ordering.
Quick checklist
The reflux valve lets air flow back through the regulator, which is useful when downstream volume must vent quickly. A regulator does not remove water or particulate; that is the filter's job.
AirTAC publishes GR-series flow as curves, not as a single rated figure, so we do not quote a rated flow, Cv or SCFM number for this unit. Tell us your inlet pressure, set pressure and required consumption, and we will confirm the flow figures from the datasheet on request before you order.
The L in the code marks the low-pressure regulator type, which regulates downstream pressure up to 0.4 MPa instead of the standard type's 0.05-0.9 MPa range - choose it when your process never needs pressure above 0.4 MPa. The K in the code means a reverse/check valve is fitted, which helps hold downstream pressure if the upstream supply drops. The fitted square gauge reads in psi; MPa and bar scales are available to order.
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.