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
Puppies and racing! Is there any better start to #SundayFunday ??? #TeamDENSO #DENSOsparkplugs
DENSO Auto Parts is at Maple Grove Raceway.
DENSO Auto Parts
Clay Millican nabs the No. 1 spot at the #DodgeNats #TeamDenso #ItsGonnaBeGreat #StompOnThatLoudPedal
DENSO Auto Parts is at Maple Grove Raceway.
We're headed to @maplegrove, where the usual rainy forecast makes way for THIS ray of sunshine and temps in the 80s… 0 2
DENSO Auto Parts
Timeline Photos We're headed to Maple Grove Raceway, where the usual rainy forecast makes way for this ray of sunshine and forecasted temps in the 80s! #DENSOpowered Matt-Angie Smith
DENSO Auto Parts is at Maple Grove Raceway.
DENSO Auto Parts
Some great reminders on the repair & maintenance of spark plugs from our partner NAPA KNOW HOW.

With all the different types of cars on the road, it is critically important to have the right spark plug for your vehicle. ...
DENSO Auto Parts
It's the 1st race of the COUNTDOWN! ProStock Driver, Angie Smith rides for DENSO this weekend at the NHRA #CarolinaNats!!!!
DENSO Auto Parts is at zMAX DRAGWAY.
DENSO Auto Parts
NHRA Carolina Nationals 2016 Results: Winner, Times and Reaction Remember this? #FlashbackFriday to last year at the NHRA Carolina Nationals when Jason Line took the victory. Will his #DENSOpowered pro stock car lead him to #1 this year?
Sunday marked the final day of the NHRA Carolina Nationals, which ...
DENSO Auto Parts
It's our mission to keep you moving through your morning commute. #WhatsUnderYourHood #DENSOpowered #TGIF
Join us as we cheer Angie and her DENSO bike on to the Winner’s Circle. Go get ‘em, @AngieSmith77 🏍⚡️🏆 #NHRA 1 7
DENSO Auto Parts
Denso sparks Angie Smith's Countdown hopes with three-race sponsorship DENSO is proud to sponsor Pro Stock Motorcycle racer Angie Smith at the upcoming NHRA Carolina Nationals.

Join us as we cheer Angie and her DENSO bike on to the Winner’s Circle. Go get ‘em, Angie! 🏍⚡️🏆
Denso Products and ...
DENSO Auto Parts
Learn how DENSO has used iridium to set the standard for today's spark plugs.
Let us remember the day and continue to fill our hearts with strength. #NeverForget #NationalDayofRemembrance 0 5
DENSO Auto Parts
Let us remember the day and continue to fill our hearts with strength. #NeverForget #NationalDayofRemembrance
DENSO Auto Parts
Even our standard spark plug is something special.

In 1975, DENSO took a leap forward in spark plug performance when we created the world's first spark plug with U-Groove ground electrode. #BestMove #KeepYouMoving #FlashbackFriday
DENSO Auto Parts
Video: Deric Kramer's EPIC, 20-Second Pro Stock Tire-Melting Burnout BURNOUTS. Need we say more? #MidDayBrainBreak
Watch as Pro Stock racer Deric Kramer boils the hides in epic fashion in his Dodge Dart on his way to winning the NHRA's unique burnout contest at the U.S. Nationals in Indianapolis.
DENSO Auto Parts
Happy Labor Day! It's been a great summer. We put a few thousand miles under our tires, where did the roads take you this summer? (Extra bonus points for road trips powered by DENSO)
DENSO Auto Parts
Deric Kramer, with his MASSIVE starting line burnout, has been crowned the DENSO Pro Stock Burnout Champion of the #ChevroletPerfUSNats

Congrats, Deric!!! #DENSOracing #NHRA
DENSO Auto Parts
#TeamDENSO looking pretty good at the #WorldsBiggestDragRace ... After Q3: Allen Johnson 🔟 : Greg Anderson 1️⃣ : Tanner Gray 2️⃣ : Bo Butner 4️⃣ #NHRA #DENSOpowered #SundayFunday
DENSO Auto Parts
*Partner Highlight* West Coast this is for you! Fast Undercar has locations up and down the West Coast.
DENSO Auto Parts
#NHRA Fan Fest in Downtown Indy is underway in anticipation of #TheWorldsBiggestDragRace happening this weekend. Who will you be cheering for? #TeamDENSO #ItsGonnaBeGreat #StompOnThatLoudPedal
DENSO Auto Parts
Happy #NationalDogDay from DENSO Auto Parts!
DENSO Auto Parts
Timeline Photos Live life a quarter mile at a time.
DENSO Auto Parts
NHRA It has officially been announced that our race, the 2018 DENSO Spark Plug NHRA Nationals, will become a 4-wide race! #DENSONats
BREAKING: Four-wide racing is heading to Las Vegas! FULL STORY:
Auto Parts shared NHRA's video.
DENSO Auto Parts
Timeline Photos Select the type of part you are looking for along with the year/make/model of your vehicle. Find your part here:
DENSO Auto Parts
Snowmobiles traveling 150MPH+ on asphalt? #YouBetcha #NHRA #LucasOilNats #DragRacing #SnowmobileRacing
DENSO Auto Parts
#DENSOpowered Matt Smith Racing blasts the field with lowest ET of the event and Angie Smith Racing continues to pave her way to right into the Top 10 here at the #LucasOilNats. Both move on to R2 of Eliminations at ...
DENSO Auto Parts
Clay Millican puts down the second quickest pass in #NHRA history during R1 at the #LucasOilNats #TeamDENSO #DENSOracing #ItsGonnaBeGreat #StompOnThatLoudPedal #PowPow25

Load More

Buy Your TT plugs today


















For a retail store or distributor near you, click below.




Find Your TT Spark Plug

Simply select the year/make/model/engine type of your vehicle.