The AirTAC GR300-08 AirTAC Air Regulator G1/4 Square Psi Gauge 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 AirTAC GR300-08 is a 300-size air pressure regulator for compressed air, fitted with a G1/4 (BSPP) female port. It does one job - holding a stable downstream pressure - and carries no filter, bowl or lubricator. This configuration is the standard regulator type with an adjustment range of 0.05-0.9 MPa (7-130 psi), an embedded square gauge reading in psi (an external round gauge in MPa, psi or bar is available as an option), and a reverse/check valve (code K) that holds the downstream setting if upstream supply is lost. It ships without a mounting bracket (code J); the GR body is also panel-mountable.
This is a genuine AirTAC part. The GR family spans sizes 200, 300, 400 and 600, so you can step port size from 1/8" to 1" as your flow demand grows, with G (BSPP) and NPT threads orderable alongside the PT standard. Operating temperature is -20 to 70 C, wider than the rest of the G-series. Flow is published as curves rather than a single rating, so ask us to confirm sizing figures from the datasheet for your application.
| Model | GR300-08 AirTAC Air Regulator G1/4 Square Psi Gauge |
|---|---|
| Series | GR300 pressure regulator |
| Port size | PT1/4" (G (BSPP) 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, 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". |
| (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. |
| 2 | Gauge scale: psi. 1 is MPa, 2 is psi, 3 is bar. |
| G | G (BSPP) 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 |
On an assembly-cell robot, the gripper air line needs a fixed, repeatable pressure so parts are held firmly without crushing. The GR300-08 regulates the 1/4" gripper supply, and the reverse/check valve holds the set pressure if the main supply drops mid-cycle.
Carton-sealing and wrapping machines run cylinders that need a steady, lower pressure than the plant main. This regulator drops the 1/4" branch feed to the set point, with the square psi gauge letting operators verify the setting at a glance.
Benchtop laboratory and test rigs use small pneumatic actuators and air bearings that are sensitive to supply swings. The GR300-08 gives the rig a stable regulated feed at its G1/4 inlet, with the wide -20 to 70 C range suiting temperature-variable rooms.
Start with the port step: this 300-size unit takes a 1/4" port, and moving to GR200 or GR400/600 changes both the connection and the flow capacity, so match the size to the air demand of the circuit rather than the pipe alone. Set the gauge scale to suit your team - this unit reads psi on the embedded square gauge, with MPa or bar scales and an external round gauge available. Choose the thread: PT is the catalogue standard, while G (BSPP) and NPT are order options, so pick the one that matches your fittings. Decide on the reverse/check valve (fitted on this unit) if the downstream setting must survive a supply loss, and on the bracket if you want panel or surface mounting - this unit omits it.
One honest note on sizing: AirTAC publishes GR flow as curves, not a single rated figure, so we cannot quote a rated flow number here. Send us your application details and we will confirm the sizing against 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 GR-series flow as performance curves rather than a single rated figure, so we do not quote a rated flow, Cv or SCFM number. Send us your application details and we will confirm the flow and sizing from the datasheet before you order.
The K in the code means a reverse/check valve is fitted: it holds the downstream pressure setting if the upstream supply is interrupted. The J means no mounting bracket is included - the GR body can still be panel-mounted, and bracket-fitted versions are available if you prefer.
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.