The AirTAC GR300-08 AirTAC Air Pressure Regulator NPT1/4 is a genuine G-series air pressure regulator. It holds a stable downstream pressure over the range 0.05 - 0.9 MPa (7 - 130 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 an AirTAC GR-series air pressure regulator for compressed air, built to hold a steady downstream pressure from a variable supply. This 300-size unit is specified with a 1/4 in NPT port, a standard regulation range of 0.05-0.9 MPa (7-130 psi), and an embedded square gauge reading in bar (psi and MPa scales are catalogue options). A reverse/check valve is fitted, and the unit is supplied without a mounting bracket; the GR series is also panel-mountable. Maximum inlet pressure is 1.0 MPa (145 psi), with an operating temperature range of -20 to 70 C - wider than the rest of the G family.
This is a genuine AirTAC part. The GR series spans sizes 200, 300, 400 and 600 with port sizes from 1/8 in to 1 in, in PT (standard), G and NPT threads, with optional low-pressure type, gauge scale choice, reverse/check valve and bracket configurations. Flow is published as curves rather than a single rated figure, so ask us and we will confirm the datasheet figures for your application on request.
| Model | GR300-08 AirTAC Air Pressure Regulator NPT1/4 |
|---|---|
| Series | GR300 pressure regulator |
| Port size | PT1/4" (NPT thread) |
| Regulating range | 0.05 - 0.9 MPa (7 - 130 psi) |
| Pressure type | Standard 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, bar 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". |
| (blank) | Standard type — 0.05 - 0.9 MPa (7 - 130 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. |
| 3 | Gauge scale: bar. 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 - 0.9 MPa (7 - 130 psi) |
|---|---|
| One size down | GR200 |
| One size up | GR400 |
| Line order | Filter first, then regulator, then lubricator |
Set a stable holding pressure for the clamp cylinders on a CNC fixture, with the check valve holding the set pressure if the shop air supply drops.
Regulate the branch feeding the bag-seal and fold actuators on a packaging line so the set pressure stays constant through the shift.
Trim the supply to the divert and stopper cylinders on a sorting conveyor so gate action stays consistent as the main header pressure wanders.
Start with the port step: the GR series runs 200/300/400/600, and larger sizes carry larger ports and higher flow capacity, so match the size to the air demand of the downstream circuit - here that is 1/4 in NPT. Then set the options that matter: gauge scale (MPa, psi or bar - this unit ships with a square bar gauge), the reverse/check valve (code K, fitted here, which holds downstream pressure on supply loss), the low-pressure L type if you need regulation only up to 0.4 MPa, and the bracket (code J omits it; the GR body is also panel-mountable). Thread is PT as standard, with G and NPT as orderable options - this unit is NPT. Note that the GR is regulation only: it has no filter bowl and no lubricator, so pair it with GF or GFR units where filtration is needed.
One honest note on sizing: AirTAC publishes regulator flow as curves, not as a single rated number, so we do not quote a flow figure here. Send us your application details and we will confirm the sizing against the datasheet curves before you order.
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 regulator flow as performance curves rather than a single rated figure, so we do not quote a flow number here. Tell us your application and we will confirm the flow from the datasheet on request before you order.
K means a reverse/check valve is fitted, which holds the downstream pressure if the upstream supply is lost. The code also decodes an embedded square gauge with a bar scale (F3); psi and MPa scales are available as order options. The J means no mounting bracket is included, though the GR body is panel-mountable.
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.