The AirTAC GR400-10 AirTAC Low-Pressure Air Regulator, PT3/8 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 PT3/8" 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 GR400-10 is a genuine AirTAC GR-series air pressure regulator in the 400 size with a PT3/8 (3/8 in) PT thread port. It does one job only: reducing and holding downstream air pressure. This is the low-pressure type (code L), so its setting range tops out at 0.4 MPa - suited to circuits that must never see full line pressure. The code also specifies an embedded square pressure gauge reading in psi and a built-in reverse (check) valve, which lets downstream air pass back through the unit and protects the circuit when upstream supply is lost. Maximum inlet pressure is 1.0 MPa (145 psi), and the GR works in ambient and media temperatures from -20 to 70 C, a wider window than the rest of the G family.
This is a genuine AirTAC part. The GR line spans four sizes (200, 300, 400, 600) with port sizes from 1/8 in to 1 in, in standard and low-pressure types, with gauge and thread options to order. Because flow is published as curves rather than a single rated figure, we confirm the datasheet and flow figures for your application on request.
| Model | GR400-10 AirTAC Low-Pressure Air Regulator, PT3/8 |
|---|---|
| Series | GR400 pressure regulator |
| Port size | PT3/8" (PT 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.
| GR400 | G-series pressure regulator, 400 body — sets the port range. |
|---|---|
| 10 | Port size PT3/8". This body offers 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. |
| (blank) | PT 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 | GR400 · PT3/8" · 0.05 - 0.4 MPa (7 - 58 psi) |
|---|---|
| One size down | GR300 |
| One size up | GR600 |
| Line order | Filter first, then regulator, then lubricator |
Pneumatic clamps on a CNC fixture that must hold workpieces at a capped pressure below full line supply. The GR400-10 regulates the clamp circuit down to a fixed setting within its 0.4 MPa range, and the check valve holds the downstream side if shop air drops.
A test bench or lab rig feeding instruments and small actuators that require a gentle, stable pressure well below the compressor output. The low-pressure type, square psi gauge and 3/8 in PT port make it a clean drop-in regulator for bench manifolds.
Sealing bars, tension rollers and low-pressure actuator banks on packaging lines that run at reduced pressure to protect film and product. The GR400-10 sets that lower pressure locally, and the reverse valve vents the circuit safely when the line is stopped.
Start with the port step: the 400 size carries a 3/8 in port, and the GR family steps through 200/300/400/600 with ports from 1/8 in to 1 in, so pick the size whose port matches your piping and whose flow curve covers your demand - ask us to confirm sizing against the application before ordering, since flow is published as curves, not a single rating. Then set the type: this unit is the low-pressure L type with a setting range up to 0.4 MPa; if your circuit needs the standard range up to 0.9 MPa, choose a GR without the L code. Decide the gauge: this configuration has the embedded square gauge in psi; external round gauges and MPa/psi/bar scales are options. Choose the thread: PT is the standard here, with G (BSPP) and NPT available as order options. The J code means no mounting bracket is fitted, and the K code adds a reverse/check valve - order the non-K version if you do not want backflow capability. The GR is also panel-mountable.
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 flow as curves rather than a single rated figure, so there is no one rated flow number we can honestly quote. Send us your inlet pressure, set pressure and expected air demand, and we will confirm the sizing from the GR400 datasheet on request before you order.
L marks the low-pressure type: the outlet setting range tops out at 0.4 MPa instead of the standard GR range up to 0.9 MPa. Inlet pressure up to 1.0 MPa (145 psi) is still fine on the upstream side - the L code limits what the regulator will pass downstream, not what it can withstand at the inlet.
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.