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Single GasketPack of 100
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AN4027-1, 18MM. These are the AN4027-1 18mm copper spark plug gaskets.

20% Discount on Box of 100
Made of solid copper to current aircraft standards. Available in 14 MM and 18 MM sizes.
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They are round, which is good, and they fit my spark plugs, which is also good.

Victor B
November 24, 2020

great value. The best price we could find.

Central A
September 2, 2020

Good price and work as expected.

Richard C
August 17, 2020

was just what I needed

July 22, 2020

Heres the deal folks...All aircraft engine manufacturers specify using a NEW gaskets when removing and replacing aviation spark plugs. If you run a Repair Station or you are an A.I. you best be using NEW gaskets (and billed on your work orders) to avoid potential liability issues. These generic branded M-674 gaskets are the correct Rockwell hardness and dimensions. We use thousands of gaskets per year and these Aircraft Spruce gaskets are now our #1 choice.
July 21, 2020

Look just like OEM. More convenient than buying a box of 100.

Donald S
June 30, 2020

no complains

David H
May 8, 2020

circular and flat, good stuff

Ernest U
April 23, 2020

I just watched a video on youtube of a fellow taking old gaskets and heating them with a blow torch to anneal them, so he could reuse them....even though they were crushed and had a raised lip. I like the idea of reusing things, but when a brand new copper gasket costs about 36 cents, that seems pretty stupid. Buy a handful of gaskets and let them sit in your tool box, and use them anytime you take a plug out... Good product, very low price.

Michael V
April 16, 2020

excellent on time shipping

Central A
April 3, 2020


Q: Will these gaskets work on Tempest spark plugs? Tempest has part number UM-674.

Yes, these copper spark plug gaskets will work on Tempest or Champion plugs.

Q: Part # 07-00877: Please inform Inside Diameter & Thickness

.71" ID or just over 18mm OD. 0.08 thick.

Q: Are the 18mm gaskets right for the O320 Lyc ?

Yes, that would be correct.

Q: Are the 18mm gaskets used for a Lycoming IO-360 with Champion plugs?

Yes, the IO-360 will use 18mm plugs.

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