The AirTAC GR400-10 NPT AirTAC Low-Pressure Air Regulator 3/8 in 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 AirTAC GR400-10 is a low-pressure air pressure regulator in the 400 size, fitted with a 3/8 in NPT port. As a regulator, it does one job: it holds a steady downstream pressure from your compressed-air supply. This low-pressure (L) configuration adjusts up to 0.4 MPa, so it suits circuits that must never see full line pressure. It handles a maximum inlet pressure of 1.0 MPa (145 psi) and operates from -20 to 70 C, a wider temperature window than the rest of the G family. The embedded square gauge (MPa scale) lets you read the setting at a glance, an external round gauge is available as an option, and a reverse/check valve is fitted so downstream pressure is held if the supply drops. A mounting bracket is included, and the GR body is also panel-mountable.
This is a genuine AirTAC part. The GR family spans sizes 200, 300, 400 and 600 with ports from 1/8 in to 1 in, in standard and low-pressure types, with your choice of gauge scale and G, NPT or PT threads. Because AirTAC publishes regulator flow as curves rather than a single rated figure, we confirm the exact flow and datasheet figures for your application on request - just ask before ordering.
| Model | GR400-10 NPT AirTAC Low-Pressure Air Regulator 3/8 in |
|---|---|
| Series | GR400 pressure regulator |
| Port size | PT3/8" (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 — square, MPa 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. |
| (blank) | Fixing bracket included. |
| (blank) | Pressure gauge fitted (blank). |
| F | Gauge shape: Square. 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. |
| 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 |
Packaging machines often need gentle, repeatable clamp or hold-down pressure well below main line pressure. This low-pressure GR400-10 lets an operator dial the clamp circuit in up to 0.4 MPa and read the setting on the square MPa gauge, while the fitted check valve holds the clamp if supply pressure dips.
Bench-top reactors, coating rigs and pilot skids frequently specify a soft, stable air supply that must not exceed a set ceiling. A 3/8 in NPT low-pressure regulator upstream of the skid caps the supply at up to 0.4 MPa, and the -20 to 70 C operating range covers unheated utility rooms.
Pneumatically piloted valves and positioners on a process line need a clean, steady pilot pressure independent of the main header. This 400-size regulator, panel-mounted or bracket-mounted with its included bracket, drops header air to the pilot pressure the actuator was specified for, with the gauge making verification at the panel simple.
Pick the GR size and port against the air your circuit actually needs: 200 through 600 step up in port size (1/8 in to 1 in) and flow capacity, so match the 3/8 in port of this 400 unit to your line and downstream demand. Choose the low-pressure (L) type only when your setpoint stays at or below 0.4 MPa; for higher setpoints up to 0.9 MPa, the standard GR type is the right decode. Select the gauge scale you want to read (MPa, psi or bar) and the thread to match your plumbing: PT is the catalogue standard, with G (BSPP) and NPT as order options - this unit is NPT. Brackets are included on GR as standard, and the body can also be panel-mounted. One honest note on sizing: AirTAC publishes regulator flow as curves, not a single rated number, so send us your application details and we will confirm the correct size 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 regulator flow as curves rather than a single rated figure, so we do not quote one number here. Send us your line pressure, set pressure and the air consumption of your equipment, and we will confirm the flow from the GR400 datasheet on request so you can size it with confidence before ordering.
The L in the code marks the low-pressure regulator type: its adjustment range tops out at 0.4 MPa, instead of the higher setpoints a standard GR reaches. Choose this type when your process or actuator must never be set above 0.4 MPa; choose the standard type for higher setpoint circuits. Both share the same 1.0 MPa maximum inlet pressure.
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.