Pneumatic fittings provide the essential link between tubes, hoses and other components in a pneumatic system.

Air fittings feature tighter seals and have lower pressure requirements than hydraulic fittings and are typically offered in various connector types. In addition to connecting pneumatic components and stopping the flow of unused ports, miniature fittings are also used to control air flow pressure and directional flow.

Choosing the Right Fittings for Your Pneumatic System

Fittings help control the force and directional flow of compressed gas or air used in pneumatic systems. One of the first considerations in choosing a connector is the type of vessel that you will be connecting to such as the flexibility of the hose or tube, as well as the inner diameter (ID) and outer diameter (OD) of the vessel to ensure an adequate seal and secure connection. Fitting material choice for your pneumatic connector is also important, including gas compatibility or resistance to heat or corrosion.
 
Other considerations in choosing the right pneumatic system connector include:

• Type of connection and the function it performs
• Operational pressure of the pneumatic system
• Operating temperature range
• P.S.I. requirements for your application
• Amount of vibration produced by the pneumatic system
• Thread type of the receiving fitting

Types of Air Hose Fittings

Plugs: Male Hose Fittings

Plugs deal with flow sizes and are rated accordingly. The most common is a quarter-inch setup, though you can also encounter half-inch and 3/8-inch options. This metric tells you how much air volume the plug can manage. There are two main types: automotive and industrial (the ones you're most likely to see). Automotive versions are T-Style and Type C, and are generally blue. Industrial models, M-Style and Type D, are usually red. ARO style models are A-style and Type B, and green in color. You can also find V-Style selections, which are purple.

If you’re looking for standard tools for around the garage, look for A-style, T-style, and M-style options. However, if you need a high-volume, low-pressure (HVLP) fitting, a V-style is what you are after. The plug works together with the pneumatic tool to control the flow of air and keep a tight seal. Common materials include brass and steel, meant to resist rust and offer a high tensile strength against pressure.

Couplers: Female Hose Fittings

The female fitting type attaches directly to the air line or compressor. Made out of the same materials as their male counterparts, these are the receiving fitting. The coupler connects to the hose, while the plug will attach to the device it’s powering. These fittings are an important factor in controlling airflow and pressure, as a small leak leads to large issues (since it’s closer to the pneumatic source). Ensure that the sizing and machining quality will provide a reliable seal for best results. You'll likely need more plugs than couplers, though the latter are more prone to wear and tear.

Purpose of Fitting

Next in line is compatibility. When it comes to air hose fittings, there's no one right answer. The part must match the task at hand. For instance, if you’re looking to airbrush your car with an HVLP system, a V-style is the only way to go. Conversely, if you’re working with pneumatic power tools, you’ll need a different type:

Especially if you're buying specific parts instead of a comprehensive fittings kit, ensure that the fitting is compatible with the task at hand.

Thread to Barb Air Fittings

Pneumatic fittings are available with a variety of thread and barb sizes to fit the plumbing specifications of your pneumatic control system. Straight Connectors, Elbows and Tees feature both single and double barbs to meet individual installation preferences. 10-32 & ¼-28 UNF threaded fittings feature our captured o-ring design which ensures a superior seal and leak resistant fit. Most of these fittings are also electroless nickel plated for corrosion resistance.

Threaded Air Fittings
A variety of configurations including Adapters, Bulkheads, Couplings, Elbows, Tees and Plugs are offered with thread sizes ranging from 10-32 UNF to ½ NPT. Our popular captured o-ring seal is standard on fittings with 10-32 & ¼-28 UNF threads and provides a superior seal ensuring a leak resistant pneumatic system fitting.

Barb to Barb Air Fittings
Barbed fittings are offered in Coupling, Cross, Elbow and Tee configurations and available for use with polyurethane tubing ranging from 1/16 ID to 3/8 ID. To meet installation preferences, both single and double barb designs are featured. These precision machined brass fittings are electroless nickel plated for corrosion resistance.

Push-to-Connect Air Fittings
Push-to-Connect fittings enable quick tubing connection and disconnection. A variety of Male and Female Connectors, Elbows and Tees feature tube ODs ranging from 1/8 to 3/8 and 10-32, 1/8 NPT or ¼ NPT threads. To ensure a leakproof fit, thread sealant is standard on all male pipe threads and the 10-32 UNF thread features an o-ring for a superior seal.

Metric Air Fittings
Several of fittings are also available with M3, M5 and M6 threads. Configurations with M5 and M6 threads feature our captured o-ring for a superior seal and leak resistant fit. Nylon gaskets are included with M3 threaded fittings.

Stainless Steel Air Fittings
Stainless Steel fittings are suitable for applications in corrosive environments where brass and Acetal are typically prohibited. Our 316L Stainless push-to-connect fittings feature FPM seals to withstand high temperatures. Barbed configurations are machined from 303 Stainless Steel and passivated for corrosion resistance.