The AirTAC GR300-08 AirTAC Air Pressure Regulator PT1/4 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 a genuine AirTAC GR-series air pressure regulator: it does one job, holding a steady downstream air pressure from a compressed-air supply, and it does nothing else - no filtration, no bowl, no lubrication. This is the low-pressure type, set up for applications that work below the standard regulator range, with a maximum regulated pressure of up to 0.4 MPa. It is sized 300 with a 1/4 in PT port, and this configuration arrives with an external round pressure gauge reading in psi already fitted, plus a reverse (check) valve so downstream pressure is held if the upstream supply drops. No mounting bracket is included, and the GR body is also panel-mountable.
The GR family is available in sizes 200, 300, 400 and 600 with matching port sizes, in standard or low-pressure (L) type, with or without a gauge (square embedded or external round, scaled in MPa, psi or bar), with or without a reverse valve, and with PT as the standard thread or G (BSPP) and NPT as order options. Maximum inlet pressure is 1.0 MPa (145 psi) and the working temperature range is -20 to 70 C, wider than the rest of the G family. 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 PT1/4 Low Pressure |
|---|---|
| Series | GR300 pressure regulator |
| Port size | PT1/4" (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 — round, 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". |
| 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). |
| C | Gauge shape: Round. 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 | 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 |
On a carton-sealing or case-packing line, delicate pneumatic clamps and hold-downs need a gentle, stable supply pressure rather than full line pressure. This low-pressure regulator lets the setter dial in the working pressure the tooling was designed for, and the check valve holds the setting if the main supply dips mid-cycle.
Analytical instruments, environmental enclosures and pilot-scale test rigs often take a small stream of compressed air for purging or sample transport, and the element being handled is sensitive to pressure spikes. A low-pressure regulator on the branch line keeps that stream steady and independent of the shop-air header.
Conveyor diverters, gate cylinders and bottle pushers on a filling line run best at a moderate, repeatable pressure so containers are moved firmly but not crushed. This regulator sits on the branch feeding those actuators, with the psi gauge giving the line technician a direct reading to set against the product being run.
Start with the port step: GR comes in sizes 200, 300, 400 and 600, and the right size depends on the air demand of the circuit downstream - pick the size whose flow curve covers your consumption at an acceptable pressure drop, and we will confirm the curves against your application before you order. Then choose the type: this is the low-pressure (L) version, regulating up to 0.4 MPa; if your process needs the full standard range, ask for the non-L variant instead. Decide on the gauge - square embedded as standard or external round, scaled in MPa, psi or bar (this unit has the round psi gauge) - and whether a reverse/check valve is needed to hold downstream pressure. Thread is PT as standard with G (BSPP) and NPT available to order, and the bracket is optional (GR is also panel-mountable). Flow is published as curves, not a single rating, so ask us to confirm sizing against the application before ordering.
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, not as a single rated number, so we do not quote a rated flow, Cv or SCFM figure. Send us your application details and we will confirm the flow curves and sizing from the datasheet on request before you order.
The L code on this unit means it is the low-pressure type, regulating up to 0.4 MPa, whereas the standard GR type covers the full range up to 0.9 MPa. If your actuators or process are specified for a low working pressure, the L type gives finer, safer control in that band; if you need the full range, order the non-L variant instead.
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.