The AirTAC GFR300-08 AirTAC Filter Regulator G1/4, Manual Drain is a genuine G-series filter regulator: water separation, 40 µm particulate filtration and balanced-type pressure regulation combined in a single body. It has PT1/4" ports, a manual drain and regulates 0.05 - 0.9 MPa (7 - 130 psi). It does not lubricate — add a GL lubricator, or order the GFC two-unit set, if downstream equipment needs oil.
The AirTAC GFR300-08 is a filter regulator: it removes water and particulate from compressed air and regulates downstream pressure in one body. This size 300 unit has a G1/4 (BSPP) port, a manual drain bowl in polycarbonate, a standard 40 um filter element, and a built-in square gauge reading in psi. The fitted check valve holds downstream pressure if the upstream supply is lost. Maximum inlet pressure is 1.0 MPa (145 psi), the regulator adjusts from 0.05 to 0.9 MPa (7-130 psi), and the operating temperature range is -5 to 70 C (non-freezing).
This is a genuine AirTAC part. The GFR series is available in sizes 200, 300, 400 and 600 with port options from 1/8 to 1 inch, a choice of manual, automatic or differential-pressure drain, 40 um or 5 um filtration, square or round gauges with MPa, psi or bar scales, and PT, G or NPT threads. Flow is published as curves rather than a single rating, so ask us to confirm the datasheet figures for your application.
| Model | GFR300-08 AirTAC Filter Regulator G1/4, Manual Drain |
|---|---|
| Series | GFR300 filter regulator |
| Port size | PT1/4" (G (BSPP) thread) |
| Filtering grade | 40 µm |
| Regulating range | 0.05 - 0.9 MPa (7 - 130 psi) |
| Pressure type | Standard type |
| Adjusting mechanism | Balanced type |
| Fluid | Compressed air |
|---|---|
| Max. working pressure | 1.0 MPa (145 psi) |
| Temperature range | -5 to +70 °C (unfreeze) |
| Drain type | Manual drain |
| Bowl material | PC |
| Pressure gauge | Fitted — square, psi scale |
| Reflux valve | Fitted (reverse flow permitted) |
Specifications follow the official AirTAC G-series air-preparation data. The regulating band is set by the drain type: automatic and differential-pressure drains regulate 0.15 - 0.9 MPa, a manual drain regulates 0.05 - 0.9 MPa. Standard type, regulating 0.05 - 0.9 MPa (7 - 130 psi). Air must not freeze in the unit. Flow curves, weight and outline dimensions are not published in our data set — ask us and we will confirm from the factory datasheet.
| GFR300 | G-series filter regulator, 300 body — sets the port range. |
|---|---|
| 08 | Port size PT1/4". This body offers 08 = PT1/4", 10 = PT3/8", 15 = PT1/2". |
| M | Drain: Manual drain — this also sets the regulating band (0.05 - 0.9 MPa (7 - 130 psi)). |
| (blank) | Standard type. Blank is standard, L is the low-pressure type. |
| (blank) | Mounting bracket included. |
| (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) | Filtering grade 40 µm. Only 40 µm (blank) and 5 µm (W) exist. |
| 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, drain, type, bracket, gauge, shape, scale, grade, thread, reflux — a blank position takes the default. Example: GFR300-08 is a 300 body, PT1/4", differential drain, standard type, bracket included, gauge fitted, 40 µm, PT thread, no 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. The GFR600 uses an aluminium-alloy bowl; the 200, 300 and 400 bodies use PC.
| This model | GFR300 · PT1/4" · 40 µm |
|---|---|
| One size down | GFR200 |
| One size up | GFR400 |
| Add lubrication | GFC300-08 (two-unit set) |
Feeding a bench-mounted pneumatic press or clamp cylinder: the GFR300-08 filters water and pipe scale out of the shop air and holds a set working pressure so the press cycles consistently, with the psi gauge giving the operator a direct setting reference.
Supplying air cylinders on a packaging or bottling conveyor: the 40 um element protects directional valves and cylinders from condensate and debris, the regulator sets the belt-tensioning pressure, and the check valve keeps the circuit charged during brief supply dips.
On a CNC or machining cell where clean, regulated air runs workholding clamps and chip-blow nozzles: the filter-regulator combination conditions the supply at the point of use, and the manual drain suits a cell that is checked at shift start.
Size 300 with a 1/4 inch port suits general machine supply lines; step up to size 400 or 600 where the flow demand is higher, or down to size 200 for compact circuits - match the size to the required flow, which we can confirm from the published curves before you order. This unit has a manual drain: an operator opens the bowl drain periodically, which suits supervised installations; choose automatic or differential-pressure drain where the unit is inaccessible. The standard 40 um element covers general pneumatic protection; specify code W for 5 um where finer filtration is needed. The square gauge is fitted here with a psi scale (MPa and bar scales are also available), and the check valve (code K) is fitted. Thread is G (BSPP); PT is the standard thread and NPT is an order option. A mounting bracket is included.
Quick checklist
The PC bowl must not be cleaned with solvents — wipe it with a dry cloth. The reflux valve permits reverse flow through the unit. A filter regulator adds no oil to the line.
AirTAC publishes flow for the GFR series as curves, not as a single rated number, so we do not quote a figure here. Tell us your application and we will confirm the flow and datasheet figures for this size 300, G1/4 unit on request before you order.
The M in the code means the polycarbonate bowl has a manual drain: an operator opens it periodically to remove collected condensate, which suits supervised installations (automatic and differential-pressure drains are available on other variants). The K code means a reverse/check valve is fitted, which holds downstream pressure if the upstream supply is interrupted.
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.