Don't Leave Your Air Coupler Wide Open.

Your onboard air system lives where dirt, mud, dust, sand and water are part of the territory. An exposed quick-connect coupler gives all of it somewhere to go.

The CMM Offroad Coupler Plug provides a simple, purpose-built way to protect an unused female air coupler until you're ready to connect your hose.

Precision CNC-machined in the USA, the Coupler Plug snaps directly into a compatible female quick-connect fitting just like the mating air fitting would. Once installed, it helps prevent contaminants from reaching the internal components of the coupler.

Check Your Fitment: Industrial (B-Style)

This Coupler Cork fits 1/4" Industrial, ISO 6150 Series B, Fed Spec A-A-59439 couplers, also known as B-Style.

Running an automotive coupler instead? Automotive 1/4" Tru-Flate (T-Style) couplers use a different plug profile and are not interchangeable with B-Style. Look for our Coupler Cork – Automotive (Tru-Flate / T-Style).

Choose Your Material

6061-T6 Aluminum
Our standard Coupler Plug provides an excellent combination of durability, corrosion resistance and lightweight performance.

7075-T6 Aluminum
For customers who want the premium option, our 7075 version provides substantially higher material strength while maintaining the same compact design.

Cerakote® Finished

Every CMM Coupler Plug receives a Cerakote finish for additional surface protection and the finished appearance you'd expect from CMM Offroad.

Available in:

• Black Cerakote

• USMC Red Cerakote

Designed for Onboard Air

Designed for compatible 1/4" quick-connect female air couplers commonly found on onboard-air systems using 3/8" air hose.

Ideal for couplers mounted on:

• Bumpers

• Underhood air systems

• Compressor installations

• Air tanks

• Air manifolds

• Exterior air connection points

• Shop and service equipment

Retain It. Don't Lose It.

Each Coupler Plug includes a stainless steel split-ring retainer, providing a durable attachment point for tethering the plug near the coupler so it's there when you need it.

Product Details

• CNC machined aluminum construction

• Choice of 6061-T6 or 7075-T6 aluminum

• Cerakote® protective finish

• Black and USMC Red color options

• Stainless steel split-ring retainer included

• Fits 1/4" Industrial ISO 6150 Series B (B-Style) couplers

• Helps block dirt, mud, sand, dust and moisture

• Quick push-in installation and removal

• Reusable

• Compact, lightweight design

• Designed and machined in the USA

Small Part. Important Job.

You've invested in your compressor, air lines, fittings and onboard-air system. Don't leave the connection point exposed.

Plug it. Protect it. Hit the trail.