How to Choose the Right Pneumatic Disconnect

Pneumatic quick disconnects are essential for connecting air hoses to tools and compressors safely and efficiently. But with multiple styles, sizes, and materials — choosing the right one can get complicated. Here’s how to make the right choice:

Step 1. Choose the right style
​There are several non-interchangeable types of air couplers and plugs. It is important to always match plug and coupler by style in the first place, not just size. View the table below to see the differences between the styles and their most common areas of usage. 

Design	Type	Description
Industrial	Type D, Milton M-Style	It will work with either “sleeve” type or “push” type couplers. No matter what the coupler looks like, if it mates with this plug, it is an “Industrial/ Milton Interchange” design. It can be identified by its 3/16” pilot and its flat-bottomed “V” – shaped ball groove. Used in general air tools, shops, compressors.
ARO	Type B	Although similar in appearance to the “Industrial/Milton Interchange” design, it can be easily distinguished because its pilot is 1/8" longer and its ball groove is nearly round. Commonly used in manufacturing, automation lines.
Tru-Flate	Type C, ​Automotive	This design is easily recognized because it has the shortest plug pilot in the industry; however, it has the widest metal section between the ball groove and the pilot. In addition, the sealing surface on the end of the plug is wider than other "interchange" designs. Mostly used in automotive shops, tire inflators.
Lincoln	Type L	The long 3/4” pilot is so distinctive it cannot be confused with other designs. It will only mate with couplers of matching designs and size. Commonly used in automotive/lube shops, grease guns.
Universal Coupler	Accepts multiple styles (plug-specific)	Mixed environments or flexibility

Step 2. Choose the right size
​Selecting the correct size is key for proper airflow and performance. Here's what to consider:
Thread Size

• Most pneumatic disconnects connect via threaded ends.
• Match the thread type and size to your hose or tool:
  • NPT (National Pipe Thread) – standard in the U.S.
  • BSP (British Standard Pipe) – used internationally

(Check the labeling on your tool or fitting for thread specs).
Flow Capacity and sizes:

• 1/4” Couplers
  → Best for light-duty air tools like nailers or inflation equipment
• 3/8” Couplers
  → Great for medium-demand tools like drills, impact wrenches
• 1/2” Couplers
  → Ideal for high-CFM tools: grinders, sanders, paint sprayers

Larger disconnects = More airflow = Better performance 

Step  3. Choose the right material
The right material depends on your specific application.
Be sure to consider whether corrosion resistance or lightweight design is more important for your setup. Use the table below to help you choose the most suitable material for your needs.

Material	Application
Steel	Heavy-duty use
Stainless steel	Harsh environments, food grade, outdoors
Brass	Corrosion resistance, long-lasting
Nylon/Composite	Lightweight, low-abuse settings

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