Part# 04-05012
MFR Model# DY90-A-12
Tube Size O.D.Fitting Dash SizePart No.


DEL fitting seals are designed to eliminate leakage due to scratches on the sealing surface, improper torquing, or poor finishes on tube ends, in high or low pressure applications. For use with AN, MS, and JIC 37 flared fittings, DEL fitting seals also reduce tube flare cracking by reducing torque needed, eliminating nose damage to the fitting, and allow reuse of hardware. Approved by NASA, SAE, Air Force, Army, Navy, and major aerospace contractors.
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WARNING: The product may contain and/or expose you to a chemical(s) or substance(s) which are known to the State of California to cause cancer and/or birth defects or other reproductive harm. www.P65Warnings.ca.gov


These things can save a lot of time and money when a fitting doesnt quite seal.

David K Verified Purchase


June 8, 2021

Fast service as always! You and mcmaster carr are the best

Carl F
May 14, 2020

Works perfectly

Robert T
March 13, 2020

A little oil leak goes a long way down the belly of an airplane. This little seal stopped the leak and gave me a little more piece of mind about my oil pressure situation.

October 13, 2018

Fantastic product. My guys use these in the US Air Force. We decided to try on our civilian GE LM6000 engine and they worked great. Prevented having to spend several thousand dollars for a new GE part.

September 11, 2017

If you are working with AN fittings I agree you should have some of these in hand. I was doing an efi conversion in a car and two expensive 90 degree fittings were leaking. Ordered these and some extras, I put it in the fitting, connected it all and that was the end to those pesky leaks. Highly recommend them.

September 9, 2017

worked as advertised. Stopped small fuel leak immediately

Pine R
October 12, 2020

Ordered these for replacement on AN fittings after fuel system repair. They are extremely fragile and I was unable to get one into proper position without damaging it. Finally put the system together without the fittings and it worked fine, no leaks.

Richard W
April 29, 2017


Please note, Aircraft Spruce'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. Aircraft Spruce 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: What material are these fittings?

They are aluminum.

Q: Are these Del fitting seals priced and sold per each seal? Or is that a package of some quantity?

These are priced and sold individually.

Q: Can they be used with aluminum fittings or are they for steel fittings?

These can be used with both steel and aluminum.

Q: Would aluminum or copper del seals be recommended for stainless JIC fittings and tubing?

Copper is recommended by the manufacturer.

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