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1000/400/500 Series MIL-C-4109 Industrial Interchange Air Swing Coupling, Female Half With Safety Vent, -04 Coupling, 1/4-18 Male NPT

Description & Features

Engineered for industrial air applications the RTC North America Ltd MIL-C-4109 Industrial Air Quick Disconnect Coupling is designed for robust performance. This coupling accepts male halves from Aeroquip FD40 Series Aeroquip FD41 Series (Aro 210) Tru-Flate and Parker (Automotive) making it versatile in various setups.

The coupling features a pin latching mechanism and a protective collar that prevents accidental disconnection. Its automatic sleeve operation allows for one-hand push-to-connect functionality simplifying the connection process. It meets MIL-C-4109 dimensional requirements for industrial interchangeability ensuring compatibility across different systems.

The coupling swivels 360deg; eliminating hose kinking and is made of durable zinc and nickel-plated steel. It is designed to provide high flow with minimal pressure drop enhancing the efficiency of air tools. The standard seal material is Buna-N known for its durability and reliability.

Additionally the coupling includes a safe automatic venting feature that releases trapped air when disconnecting ensuring a secure and efficient operation. Rated for a maximum operating pressure of 300 PSI for Milton models it is suitable for demanding industrial environments.

Supplier Part Number: R20500317

MPN: C1ZY89

Specifications

A 2.66	B 0.79	Coupling Size -04	Brand RTC North America Ltd	Brand RTC North America	Pack Size 1.00	UOM EA	Seal Material Buna-N	Supplier Part Number R20500317	Thread 1 1/4-18	Thread Sealant No	Alternate Part Numbers Alternate Part Number C1ZY89, Alternate Part Number MI-08754630, Alternate Part Number MINO-00691X96667	Product Weight 0.22 lbs

Similar Products

Model Number	Coupling Size	Thread 1	Seal Material	A	B	Price	Action
20500317 MIL-C-4109 Industrial Air QD	-04	1/4-18	Buna-N	2.66	0.79
20500318 MIL-C-4109 Industrial Air QD	-04	3/8-18	Buna-N	2.66	0.79

Product Questions & Answers (2)

Question by: Hubert G on May 7, 2025, 6:24 AM

got a pile of different air plugs in the shop. is this female coupler picky, or will it hook up with the common ones

Answer by: Customer Support on May 8, 2025, 11:31 AM

For interchangeability, it is built to MIL-C-4109 dimensions and it is meant for industrial air quick disconnect use when the male half type is not known. It accepts male halves from Aeroquip FD40 Series, Aeroquip FD41 Series (Aro 210), Tru-Flate, and Parker (Automotive).

Question by: Keith W on Feb 24, 2026, 5:41 PM

does this female half work with Tru-Flate and Parker automotive style male halves, or is it only gonna fit the Aeroquip stuff?

Answer by: Customer Support on Feb 25, 2026, 9:54 PM

Accepts male halves from Aeroquip FD40 Series, Aeroquip FD41 Series (also known as Aro 210), Tru-Flate, and Parker Automotive. That cross-compatibility is one of the main selling points on this coupling, so if you're running a mixed shop or just aren't sure what male half you're working with, it'll cover you across all four of those styles.