Creative solutions.


  • power-text
    The Iridium TT’s revolutionary 0.4 millimeter center electrode means significantly improved combustion and fewer misfires – optimizing power output like never before.







  • economy-text
    Invented by DENSO, the Iridium TT
    Twin-Tip Technology enables larger spark concentration and explosion, delivering more complete combustion, which translates to more superior
    fuel economy.




  • endurance-text
    The unparalleled Iridium TT spark plug is tested to last well beyond 100,000 miles, with minimal loss to performance, contributing to more overall lifetime savings than any plugs available today.










The Iridium TT Twin-Tip Technology delivers far less obstruction to the spark allowing an omni-directional explosion. This minimizes the quenching effect and results in a more effective, more complete combustion. Better combustion means more power and better fuel economy, as fuel is burned more efficiently with each piston firing. The large center and ground electrodes seen on a Standard Plug increases “quenching” of the explosion, meaning the spark explosion is restricted by the electrodes above and below the gap, allowing it to spread to either side, but not grow with full range.

For complete combustion, the Iridium TT’s two tips allow the spark plug to create the largest spark concentration and explosion, which translates into more power and superior fuel economy than any other plug.


With this unique design, there are literally two “tips”: a 0.4-millimeter Iridium center electrode, and a 0.7-millimeter Platinum ground electrode. DENSO’s patented Twin-Tip technology was first used on original equipment spark plugs for luxury and performance cars. Now, that technology is available to everyone.

0.4-Millimeter Center Electrode

The 0.4-millimeter center electrode has a low required voltage and high ignitability, that means your vehicle experiences less interference to spark growth (quenching), fewer misfires and significantly improved combustion, optimizing power output and fuel economy – getting you farther with less gas.

Developed with DENSO’s own optimized Iridium alloy; this is the smallest mass-produced center electrode available today.


DENSO selected Iridium and engineered it with Rhodium to build the most durable alloy for spark plugs. The patented formula has the highest concentration of Iridium of any spark plug and outperforms in the most severe engine temperatures resisting oxidation and voltage wear for over 100,000 miles.

A member of the platinum family, Iridium is the most corrosion-resistant metal known on earth.

360-Degree Laser Welding

Precision welding by DENSO’s state-of-the-art 360-degree laser welding technology allows the Iridium TT’s twin tips to deliver omni-directional ignition, contrary to the flat “sandwich” ignition offered by other spark plugs in the market. The superior ignition of the Iridium TT means each spark burns the fuel more efficiently, giving your vehicle more power and better fuel economy.

To provide the best plug in the market, DENSO developed a proprietary 360-degree laser welding process : the result is the highest quality bond that ensures structural support for the Iridium center electrode, which resists wear and oxidation, even in the harshest combustion environments.










The Original Twin-Tip








  • • Titanium-enhanced alloy ground electrode
    • 1.1mm platinum center electrode
    • Minimum-quench electrode design



  • • Improved fuel economy
    • Faster starts
    • Enhanced flame propagation for increased engine efficiency










Quality, Reliability and Value. At DENSO we’ve taken everything we have learned as an OE manufacturer and applied it to our aftermarket product lines. Every component that leaves our factories has been designed with precision, manufactured to OE standards and subjected to rigorous safety and performance tests.

At DENSO, we’re constantly striving to break new ground with innovative solutions for today’s demanding automotive needs. All of our aftermarket products are built to OE-standards and incorporate the latest upgrades —
a promise only an OE manufacturer can make.

DENSO products are manufactured to give you the right part and the right fit … the first time, every time.

DENSO Auto Parts
Timeline Photos We've spent over five decades perfecting our technology and processes...not too shabby.
Come for a chance to meet & greet with one of NHRA'S top drivers @ClayMillican at @AAPEXShow #AAPEX16 1 9
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Timeline Photos Hey NHRA fans!!! Racing is underway in Texas for the AAA Texas NHRA FallNationals at Texas Motorplex. While you watch the races, be sure to enter our DENSO 2 WIN Sweepstakes! To enter:

What You’ll Win:
- Tickets to ...
Come for a chance to meet & greet with one of NHRA'S top drivers @ClayMillican at @AAPEXShow #AAPEX16 4 11
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Timeline Photos A trade show is not complete without a celebrity appearance!

Join us at AAPEX Show - Automotive Aftermarket Products Expo Nov 1-3 for a chance to meet & greet with one of NHRA'S top drivers Clay Millican.
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Timeline Photos Did you check out the episode of Two Guys Garage featuring Federated Auto Parts and DENSO Iridium TT Spark Plugs? Check it out if you missed it:
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Timeline Photos We're only a few weeks away until the end of the NHRA season. Have YOU entered to win the DENSO 2 WIN sweepstakes??? Visit to enter.

What You’ll Win:
- Roundtrip airfare for you and a guest from anywhere ...
Countdown to AAPEX 2016!!! Join us at the AAPEX Show - Automotive Aftermarket Products Expo November 1-3. #AAPEX2016 0 3
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DENSO Auto Parts Countdown to AAPEX 2016!!! Join us at the AAPEX Show - Automotive Aftermarket Products Expo November 1-3.
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Timeline Photos Greg Anderson gets by in 2nd round of eliminations -- just before the sprinkles start. Racing currently on hold, again... Anyone spot that DENSO decal?
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Racing finally underway here at Maple Grove. After 2 full days of rain, this is the first complete pass down the track in Funny Car. Trying to squeeze in all they can before the rain comes back this afternoon. #NHRA
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Timeline Photos If this showed up on your driveway, would you drive it?
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Timeline Photos DENSO First Time Fit Alternators provide perfect mounting with no belt/pulley alignment issues. Watch more:
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Allen Johnson Racing HEY NHRA FANS- Allen Johnson will be signing autographs on behalf of DENSO at the O'Reilly Auto Parts booth **TOMORROW** from 12:30-1:00pm (time subject to change in the event of race delay, etc)!
#NHRAonFOX #NHRACountdown #AAAMidwestNats
DENSO Auto Parts shared ...
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DENSO Auto Parts's cover photo DENSO Auto Parts updated their cover photo.
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Timeline Photos Hey DENSO fans, we know our parts are popular and you can't wait to buy some and install them on your vehicles. Just a reminder, DENSO does not sell directly to consumers!

*** Be sure to check out the new ...
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NHRA Jason Line takes down his teammate Greg Anderson in the final to win in Charlotte! #CarolinaNats #NHRACountdown #GoOnYello
DENSO Auto Parts shared NHRA's video.
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Timeline Photos Maintenance Monday! DENSO's Direct Ignition Coils offer these top 3 benefits:
(#1) Eliminates phantom misfires (#2) Small in size, light in weight and easy to install (#3) Provides maximum available voltage under all operating conditions
Find out more:
DENSO Auto Parts
Timeline Photos It's another race day for DENSO Powered drivers! The 9th Annual NHRA Carolina Nationals starts TODAY! More info:
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Timeline Photos "Show us your DENSO" Promotion - SHOW US YOUR DENSO for a chance to win an exciting prize pack for free.

Here is how to enter: #1) Snap a photo of any DENSO part from under your hood #2) Post ...
DENSO Auto Parts
Timeline Photos "I’m so blessed to have sponsorship like I do, because if I didn’t have the help I do from PEAK Antifreeze & Motor Oil, Mickey Thompson Performance Tires & Wheels, K&N Filters, Denso Spark Plugs, and all the product sponsors, ...
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Timeline Photos POWERED BY DENSO. A category all in its own.

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