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Brass Push-In Tube Fitting, 0.25 Tube OD to 1/4-18 Female NPT, Straight Bulkhead

Description & Features

Designed for quick, tool-free tube connections, this Brass Push-In Tube Fitting, 0.25 Tube OD to 1/4-18 Female NPT, Straight Bulkhead from Alkon Corp provides a reliable, leak-proof seal in pneumatic and fluid line installations. Brass construction offers durability across a wide range of industrial environments, with Buna-N O-rings standard for consistent sealing performance.

The push-in mechanism grips the tube automatically upon insertion, pulling force or line pressure only tightens the hold. A positive tube stop and interior camming surface work together to prevent leakage under working conditions. Pre-applied Teflon-based sealant on all male threads simplifies installation. Compatible with polyurethane tubing (90 durometer and above), polybutylene tubing, and soft metal tubing. Rated for use from -10°F to 200°F, and suitable for vacuum service.

SKU: AQ86-P-4X4

Supplier Part Number (MPN): AQ86-P-4X4

Alternate Part Numbers: C1CK58, MI-00293988, MINO-00034F41667

Specifications

A 1.46	D 0.63	Brand Alkon Corp	Brand Alkon Corp	Pack Size 1.00	UOM EA	Supplier Part Number AQ86-P-4X4	Thread 1 1/4-18	Thread 2 1/2-20	Tube O.D. 0.25	Tube O.D. 0.25	Alternate Part Numbers Alternate Part Number C1CK58, Alternate Part Number MI-00293988, Alternate Part Number MINO-00034F41667	Product Weight 0.10 lbs

Similar Products

Model Number	Tube O.D.	Thread 1	A	Thread 2	D	Price	Action
AQ86-P-4X4 Brass Push-In To Female NPT Bulkhead	0.25	1/4-18	1.46	1/2-20	0.63
AQ86-P-6X4 Brass Push-In To Female NPT Bulkhead	0.38	1/4-18	1.89	5/8-18	0.99

Product Questions & Answers (2)

Question by: Travis A on Sep 21, 2025, 1:33 PM

If I'm using this bulkhead fitting with some soft metal tubing, will it still hold okay?

Answer by: Customer Support on Sep 22, 2025, 6:35 PM

This fitting is compatible with soft metal tubing, as well as polyurethane (90 durometer and above) and polybutylene tubing. The push-in design grips the tube automatically upon insertion and only tightens with pulling force or line pressure.

Question by: Kent R on Jun 25, 2025, 7:34 AM

got 1/4" OD poly tube, does this fitting actually bite and seal without clamps or anything?

Answer by: Customer Support on Jun 26, 2025, 8:05 PM

Once the tube is pushed in, the gripping teeth grab the outside of the tubing and a Buna-N O-ring seals on the tube OD. Pulling on the tube or having pressure in the line only tightens the grip because the insert cams in deeper, and the tube bottoms on a positive stop for support.