The AirTAC GFR300-08 AirTAC Filter Regulator NPT1/4 5um Manual Drain is a genuine G-series filter regulator: water separation, 5 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 holds downstream pressure steady, with both jobs done in one body. This configuration is built with a 1/4 in NPT port, a 5 um filter element (code W, finer than the standard 40 um grade), a manual drain on the polycarbonate bowl, a round pressure gauge reading in bar, and a built-in reverse/check valve (code K). No mounting bracket is fitted. Maximum inlet pressure is 1.0 MPa (145 psi), the regulator range for this manual-drain unit is 0.05-0.9 MPa (7-130 psi), and the operating temperature range is -5 to 70 C, non-freezing.
This is a genuine AirTAC part in the GFR300 series. The GFR filter-regulator line runs from size 200 to 600 with ports from 1/8 to 1 in, and can be ordered with 40 um or 5 um filtration, differential-pressure, automatic or manual drains, embedded square or external round gauges with MPa, psi or bar scales, PT, G or NPT threads, and with or without a bracket and reverse/check valve. Flow is published as curves rather than a single rated figure, so ask us to confirm the datasheet and sizing for your application on request.
| Model | GFR300-08 AirTAC Filter Regulator NPT1/4 5um Manual Drain |
|---|---|
| Series | GFR300 filter regulator |
| Port size | PT1/4" (NPT thread) |
| Filtering grade | 5 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 — round, bar 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. |
| J | Supplied without bracket. |
| (blank) | Pressure gauge fitted (blank). |
| C | Gauge shape: Round. C is round, F is square. |
| 3 | Gauge scale: bar. 1 is MPa, 2 is psi, 3 is bar. |
| W | Filtering grade 5 µm. Only 40 µm (blank) and 5 µm (W) exist. |
| 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, 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" · 5 µm |
|---|---|
| One size down | GFR200 |
| One size up | GFR400 |
| Add lubrication | GFC300-08 (two-unit set) |
On a CNC fixture with air-actuated clamps, this unit filters machining-air moisture and swarf down to 5 um and holds a steady regulated supply to the clamp cylinders, so clamp force stays consistent part after part. The check valve keeps the circuit from venting if the main supply dips mid-cycle.
On a carton packaging line, diverters, pushers and sealing jaws run off a shared air drop. This filter regulator cleans the supply and holds the pressure the cylinder circuit was set up for, while the manual drain lets an operator bleed collected water from the bowl at shift start.
A gripper and clamp circuit on a robotic weld cell needs clean air and a stable set pressure at the tool. Mounted at the cell drop with a 1/4 in NPT connection, this unit conditions the supply to the end-effector, and the round bar gauge gives a local reading for setup and checks.
Start with the size and port: this is a size 300 unit with a 1/4 in NPT port; larger sizes (400, 600) carry bigger ports and more flow, and because flow is published as curves rather than a single rating, ask us to confirm sizing against your application before ordering. This code already fixes several choices: 5 um filtration instead of the standard 40 um, a manual drain instead of the differential-pressure default or the automatic option, a round bar gauge, and a reverse/check valve, with no mounting bracket. If you would prefer the 40 um element, an automatic drain, a square gauge on an MPa or psi scale, a PT or G thread, or a bracket, those are order options within the same GFR300 series.
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 rather than a single rated figure, so we do not quote a flow number for this unit. Tell us your application and required port size, and we will confirm the flow curve and full datasheet figures for the GFR300-08 on request before you order.
This unit is coded M for a manual drain: collected water is emptied from the polycarbonate bowl by hand, which suits lines that are checked regularly. The same GFR300 body can be ordered with an automatic drain (code A) or the differential-pressure drain (blank). Note that the drain type also sets the regulator range, which is 0.05-0.9 MPa (7-130 psi) on this manual-drain configuration.
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.