The AirTAC GFR300-08 AirTAC Filter Regulator NPT1/4, 5 um 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 regulates downstream pressure in a single body. This configuration is the 300 size with a 1/4 in NPT port, fitted with the fine 5 um filter element (code W) for cleaner air than the standard 40 um grade, a manual drain for controlled bowl purging, and the embedded square gauge on the MPa scale for direct setting of the regulated pressure. The standard regulator adjusts from 0.05-0.9 MPa (7-130 psi); maximum inlet pressure is 1.0 MPa (145 psi) and the working temperature range is -5 to 70 C (non-freezing). The polycarbonate bowl suits the 300 size, and the J code means no mounting bracket is supplied.
This is a genuine AirTAC part. The GFR300 belongs to the GFR filter-regulator family, which spans the 200, 300, 400 and 600 sizes with port options from 1/8 in to 1 in, a choice of differential-pressure, automatic or manual drains, 40 um or 5 um filtration, gauge styles and scales, and PT, G or NPT threads. Flow is published by AirTAC as curves rather than a single rated figure, so we confirm the datasheet figures for your application on request.
| Model | GFR300-08 AirTAC Filter Regulator NPT1/4, 5 um |
|---|---|
| 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 — square, MPa scale |
| Reflux valve | Not fitted |
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). |
| F | Gauge shape: Square. C is round, F is square. |
| 1 | Gauge scale: MPa. 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. |
| (blank) | No reverse-flow valve (the default). |
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) |
Feeds the air cylinder circuit of a bench press or stamping fixture: the 5 um element keeps solenoid valves free of particulate while the regulator holds a steady setting for consistent forming strokes, with the MPa gauge giving the operator a direct read of the set pressure.
Supplies the diverters, clampers and bag-forming cylinders on a packaging conveyor line, where the manual-drain bowl is purged at shift start and the regulator keeps actuator speed and clamping force repeatable across the line.
Conditions the shop-air feed to a CNC machining centre's tool-changer and clamping circuits: the fine 5 um grade protects the pilot valves of the tool changer, and the regulated output matches the machine tool builder's specified supply pressure.
Step up or down through the 200/300/400/600 sizes and their port steps (1/8 in to 1 in) to match the air demand of the circuit; the 300 size with its 1/4 in port is the middle step for general machine supply. Choose the drain to suit access: manual (this unit) when an operator can purge the bowl on a schedule, automatic or differential-pressure where unattended draining is preferred. Choose the 5 um element (this unit) where downstream valves and instruments need cleaner air, or the standard 40 um for general supply. Gauge scale is MPa on this unit, with psi and bar scales and an external round gauge as options; thread is NPT here, with PT as the standard and G as an order option; a mounting bracket can be added if the J (no bracket) build does not suit the panel. Because flow is published as curves rather than a single rating, ask us to confirm sizing against your application before ordering.
Quick checklist
The PC bowl must not be cleaned with solvents — wipe it with a dry cloth. Without the K option, air cannot flow back through the unit. A filter regulator adds no oil to the line.
AirTAC publishes flow for the GFR300 as curves, not as a single rated number, so we do not quote a rated flow, Cv or SCFM figure. Tell us your application and required flow, and we will confirm the datasheet curve figures for this exact configuration before you order.
The M code in GFR30008MJF1WT specifies a manual drain: condensate collected in the polycarbonate bowl is purged by hand, which suits stations that are checked on a regular schedule. The same GFR300 family is also available with an automatic drain or the default differential-pressure drain for unattended condensate removal, and the manual-drain build carries the wider 0.05-0.9 MPa (7-130 psi) regulation range.
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.