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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

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

Product Questions & Answers 2

Product Questions & Answers

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

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

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

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

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

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

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Model Number	Coupling Size	Thread 1	Seal Material	A	B	Price	Buy Now
20500317	-04	1/4-18	Buna-N	2.66	0.79
20500318	-04	3/8-18	Buna-N	2.66	0.79