Part# 491-3
MFR Model# 491-3
DescriptionTubeThreadPart No.
Aeroquip 491 Hose Fitting3/163/8-24491-3


Aeroquip 491 hose fittings consist of an AN818 style nut, an externally threaded 37 nipple and an internally threaded hose socket. Fittings of sizes 3 through 6 have nuts and nipples of cadmium plated steel. Nuts and nipples for size 8 and larger are of anodized aluminum. Fittings conform to MS24587.
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Peter S Verified Purchase


January 17, 2024

Up dating oil pressure line

Robert A Verified Purchase


October 23, 2023

As usual. Aeroquip does well

Randol W
April 21, 2021

Excellent product and quality. Shipped quickly as well

Scott J
January 20, 2021

The RIGHT part I needed for assembling the oil-pressure sensor hose, using Aeroquip-303 hose. Thanks, AC-S!

Dennis K
October 26, 2020

Seems to hold up well. Be sure to use a mandril when inserting the ferrels or else youll score the inner rubber tubing. Will definitely use again.

Joe S
August 31, 2020

Good quality as expected Over priced as expected

Sam O
December 19, 2019

Fittings were a snap to install on the associated 303 hose. Pleased with my order.

Micheal D
November 14, 2019

As others have noted, easy to install, especially if you first look at EAA video on how to. The mandrel for the size you want is a little expensive but very necessary. No can do without the correct size mandrel.

Eric A
November 5, 2018

Great project part for student projects.

Ed B
October 16, 2017


Please note,'s personnel are not certified aircraft mechanics and can only provide general support and ideas, which should not be relied upon or implemented in lieu of consulting an A&P or other qualified technician. assumes no responsibility or liability for any issue or problem which may arise from any repair, modification or other work done from this knowledge base. Any product eligibility information provided here is based on general application guides and we recommend always referring to your specific aircraft parts manual, the parts manufacturer or consulting with a qualified mechanic.

Q: When referencing the tube size, is this an ID or OD measurement?

The tube size is in reference to the O.D. of the hard line the 303 hose, & 491 fitting, is replacing.

Q: Can these Aeroquip 491 fittings be used on Stratoflex 111 hose?

You will need to use the 300 series Stratoflex fittings for the Stratoflex 111 series hose. The 491 series fittings are for the 303 Aeroquip hose series.

Q: What is the difference between 491 and 471? Will be using 303 hose.

Material finish. 471 are all anodized aluminum. 491 Material & Finish:Nut and nipple, sizes 3 through6, cadmium-plated steel. Nut and nipple sizes 8 and up, and socket, anodized aluminum