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 an AirTAC GR-series air pressure regulator in the 300 size with a 1/4 in NPT port. This is the low-pressure (L) type, which regulates downstream pressure up to 0.4 MPa, and it carries the C1 gauge option: an external round pressure gauge with an MPa scale. The maximum working (inlet) pressure is 1.0 MPa (145 psi), the operating temperature range is -20 to 70 C (the widest in the G family), and a mounting bracket is included. As a regulator-only unit it performs one job - holding a stable downstream pressure - with no filter element, no bowl and no drain.
This is a genuine AirTAC part. The GR series is available in sizes 200, 300, 400 and 600 with ports from 1/8 to 1 in, in standard or low-pressure types, with G (BSPP) or NPT threads as order options alongside the PT standard, optional reverse/check valve (K), gauge scale choices (MPa, psi or bar) and a no-bracket (J) variant. Flow is published as curves rather than a single rated figure, so we 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 | Fixing bracket included |
| Fluid | Compressed air |
|---|---|
| Max. working pressure | 1.0 MPa (145 psi) |
| Temperature range | -20 to +70 °C |
| Pressure gauge | Fitted — round, MPa scale |
| Reflux valve | Not fitted |
| 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. |
| (blank) | Fixing bracket included. |
| (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. |
| 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, 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 |
End-of-arm grippers and light clamps run at deliberately low pressures so delicate parts are not crushed. The GR300-08 holds a gentle, stable downstream setting up to 0.4 MPa on a 1/4 in line, with the round MPa gauge giving the operator a direct readout at the cell.
Bench rigs and lab fixtures need a repeatable, low set point that stays put through the day. Mounted on the panel with the included bracket, the low-pressure regulator keeps test fixtures supplied at a controlled pressure, and the -20 to 70 C range covers unheated rooms and cold stores.
Weld and assembly fixtures often clamp with low-pressure air to avoid marking finished surfaces. The GR300-08 regulates the clamp circuit independently of the main 1.0 MPa shop-air header, and the K reverse/check valve option can be ordered where the downstream pressure must be held if supply is lost.
Start with the port step: the 300 size with a 1/4 in NPT port suits lines where the required flow falls in the middle of the GR range; step up to 400 or 600 for larger consumers, down to 200 for compact circuits. Because flow is published as curves rather than a single rating, ask us to confirm sizing against your application before ordering. Choose the low-pressure (L) type when the downstream setting must stay at or below 0.4 MPa; the standard GR type covers 0.05-0.9 MPa. Then settle the remaining decodable options: gauge scale (MPa, psi or bar, round external or embedded square), thread (PT is the standard; G and NPT are order options), bracket (J deletes it) and the K option if a reverse/check valve is wanted.
Quick checklist
Without a reflux valve, air cannot flow back through the regulator — order the K option if reverse flow is required. A regulator does not remove water or particulate; that is the filter's job.
AirTAC publishes GR-series flow as characteristic curves, not as a single rated figure, so there is no honest one-number answer we could print here. Tell us your line pressure, set point and the consumers on the circuit, and we will confirm the flow figures from the datasheet for the 300 size before you order.
L is the low-pressure regulator type: it regulates downstream pressure up to 0.4 MPa. The standard GR type (no L in the code) covers a 0.05-0.9 MPa setting range. Both share the same 1.0 MPa (145 psi) maximum inlet pressure, so pick L when your process set point sits in the lower band and you want finer control there.
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.