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 supply of up to 1.0 MPa (145 psi). Its adjustment range is 0.05-0.9 MPa (7-130 psi), and the C3 code means an external round gauge on a bar scale is fitted so operators can read and set the working pressure at a glance. The K code adds a reverse (check) valve, and this 300-size unit carries a 1/4 in NPT port; PT is the standard thread and G/NPT are order options. As a GR unit it does regulation only - there is no filter, no bowl and no drain - and it works across -20 to 70 C, a wider temperature window than the rest of the G family.
This is a genuine AirTAC part in the GR300 size class. The GR line runs from size 200 through 600 with larger ports and higher flow capacity at each step, and options include a low-pressure type (L), square embedded or round external gauges on MPa, psi or bar scales, a reverse/check valve, and panel mounting - GR units are also panel-mountable and this one ships with a bracket. We do not quote a single rated flow figure because AirTAC publishes flow as curves; ask us and we will confirm the datasheet figures against your application.
| 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 | Fixing bracket included |
| Fluid | Compressed air |
|---|---|
| Max. working pressure | 1.0 MPa (145 psi) |
| Temperature range | -20 to +70 °C |
| Pressure gauge | Fitted — round, 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. |
| (blank) | Fixing bracket included. |
| (blank) | Pressure gauge fitted (blank). |
| C | Gauge shape: Round. 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 working pressure for a bench pneumatic press or clamping fixture, with the bar-scale gauge letting operators verify the setpoint before each cycle.
Regulate the 1/4 in air drop feeding a packaging machine's cylinders and actuators, keeping the downstream pressure steady as the supply line fluctuates.
Feed a conveyor line's divertor and stopper cylinders from a regulated branch, with the check valve holding the setting against back-pressure from downstream valves.
Start with the port and size step: this 300-size unit has a 1/4 in NPT port, and moving to 400 or 600 gives larger ports for higher air demand - size up rather than undersize. Set the pressure span you actually need: the standard GR covers 0.05-0.9 MPa (7-130 psi), while the low-pressure type (L) is the choice if your process tops out at 0.4 MPa. Pick the gauge to match your team: square embedded or round external, on MPa, psi or bar scales - this unit is fitted with a round gauge on bar. Choose the thread to suit your piping: PT is the standard, with G (BSPP) and NPT as order options. The K code here means a reverse/check valve is already fitted; leave it off if your circuit handles that elsewhere. A mounting bracket is included, and GR can also be panel-mounted. One honest note on sizing: flow is published as curves, not a single rating, so send us your air demand and line pressure and we will confirm the right size from the datasheet 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 number. Tell us your air demand and line pressure and we will confirm the sizing from the datasheet on request before you order.
C3 means an external round gauge on a bar scale is fitted, so you can read and set the outlet pressure directly. K means a reverse (check) valve is fitted to hold the setting against back-flow. The unit also includes a mounting bracket and can be panel-mounted.
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.