HKS M-Series Spark Plugs

(95 customer reviews)


677 sold


Ultimate spark plug “M”.

Ignitionability, durability, anti-insulation are all reinforced. HKS has made the best plug for both tuning engines and stock engines.



  • 0.6mm Iridium Alloy Center Electrode
    Iridium alloy center electrode reduces voltage requirement and improves ignition performance and durability.
  • Outer Electrode with Platinum Chip
    The outer electrode incorporates a square platinum chip which improves durability, and combining with the iridium center electrode boosts ignition performance.
    The outer electrode features a shortened tip design and tapered shape while maintaining the necessary space for proper ignition.
  • Short Type Outer Electrode (Anti-Vibration)
    The outer electrode has been shortened and engineered with the ideal shape to decrease weight for resistance against vibration. This anti-vibration design improves longevity of the outer electrode.
  • Thermal Edge
    After long idling or under various combustion conditions, carbon buildup can occur causing misfires. The thermal edge of the ceramic insulator discharges to help decrease carbon deposits.
  • Spark Support Gap
    Discharge occurs in the spark support gap (space between the tip of insulator and the base of the outer electrode) to help prevent carbon buildup.

Performance and Efficiency

  • Increased Ignition Performance
    Decreased voltage requirement strengthens ignition performance under harsh conditions like lean mixture or high boost pressure.
  • Improved Durability
    New material and design improve durability which allows for use under hard combustion conditions like continuous high load during circuit driving or aggressive tuning.
    * Improper combustion condition and wrong heat range selection may cause damage to the spark plug.
  • Decreased Carbon Deposits
    Thermal edge and spark support gap help prevent carbon buildup for better ignition under various combustion conditions.

Heat Range Conversion Chart

HKS 25 30 35 40 45 50 52.5 55
DENSO社 16 20 22 24 27 31 32 34
NGK社 5 6 7 8 9 10 10.5 11

* Above information is the reference for heat resistance.

Weight 1 lbs
Dimensions 3.9 × 1 × 1 in

Model Year

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95 reviews for HKS M-Series Spark Plugs

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Based on 95 reviews
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  1. David Chung (verified owner)

    Plugs got here fast!

  2. Jean M. (verified owner)

    Great price and fast shipping!

  3. Anonymous (verified owner)

    Exactly what I needed and product came fast from the other side of the country

  4. Yeng Lor (verified owner)

    Fast shipping can’t wait to order more off kdtuners

  5. BEN WAXMAN (verified owner)

    plugs worked as expected

  6. Andrew Osmond (verified owner)

    Super fast shipping. Everything packaged well and secure. I will be purchasing more things from kdm tuners!

  7. justin sexton (verified owner)

    Best price around for the plugs and quick shipping.

  8. Francisco Caban (verified owner)

    Exelent seller, exelent sparks plugs recommended 100%

  9. Anonymous (verified owner)


  10. Christopher Mayo (verified owner)

    Josh and KDM was very helpful and accomodating to make sure I got my plugs ASAP. They even went out there way on the weekend to ensure I would get it by end of Sunday! From now on I will be making all available purchases for my VT with KDM.

  11. jeffrey h. (verified owner)

    Fast shipping. Messaged me after I asked a question. 10/10

  12. Martin P. (verified owner)

    Great product

  13. Stephen Surita (verified owner)

    Great price

  14. Carlos T. (verified owner)

    Fast shipping best prices

  15. christopher fox (verified owner)

    Excellent service!! Now if only they’d send me a cylinder head lol

  16. Ross C. (verified owner)

    This company is incredible! Super quick updates and fast order processing. Will definitely be back!

  17. Mark Cook (verified owner)

    Best deal I had found on a genuine product. Thank you guys for more than reliable service. A product that exceeds my expectations.

  18. Anonymous (verified owner)

    Super gast delivery!

  19. Quentin (verified owner)

    Packed well and shipped quickly, have yet to install but plugs seem to be in perfect condition.

  20. Mike D. (verified owner)

    Excellent price showed up quickly

  21. Axel (verified owner)

    Got probably the best deal on any website and I got them very fast. That’s why i like purchasing from here

  22. Kevin wilson (verified owner)

    You guys are the best with fast shipping

  23. Anonymous (verified owner)

    Quick install ready and fast shipping!

  24. Alec Combs (verified owner)

    I received my spark plug but I’ve not received my braided gas lines. I’d really like to know where they are.

  25. Jakob Johnson (verified owner)

    Came faster than the parts that I ordered from pierce motorsports. They shipped on the same day

  26. Jaramieh Kaiser (verified owner)

    Better plugs all around for the Forte GT. Shipped extremely fast!

  27. TODD MAGANA (verified owner)


  28. Paul Fulmore (verified owner)

    Better price than their competitors and shipped faster as well

  29. Zachary Dobbins (verified owner)

    Great product

  30. James Sim (verified owner)

    This site and people are amazing

  31. Chad M. (verified owner)

    Is good

  32. Ethan K. (verified owner)

    Great communication and shipping time

  33. Yomar J. Rodriguez (verified owner)

    Excellent service and communication

  34. Rayquan (verified owner)

    Excellent service product was in great condition and no problems

  35. Coleen clemens (verified owner)

    Worked great!

  36. Daniel Hill (verified owner)

    Good stuff

  37. ED SOTOMAYOR (verified owner)

    Excellent plugs! Fast delivery! Super helpful info on which plugs one should use on their setup. Thanks!

  38. Timothy Franklin (verified owner)

    Great plugs fast shipping decent price .

  39. Jose Iva Villalobos (verified owner)


  40. Joselito M. (verified owner)

    Awesome place to buy parts! Customer service is A1! Will be back again for future needs ????????????????????????

  41. Eddie Sotomayor (verified owner)

    Excellent plugs! The info breakdown for what’s best for your set up is super helpful. Thanks. Great price and fast shipping!

  42. Anonymous (verified owner)

    Excellent product! Slow delivery time, but that’s thanks to ‘rona.

  43. Anonymous (verified owner)

    best online shop out there, if you buy from anyone else it would be a mistake……

  44. logan mcdonald (verified owner)

    Im sure they will be great but i haven’t received them yet

  45. devon w. (verified owner)

    Best plugs for tuned cars hands down thanks kdm tuners fam for the support!

  46. John (verified owner)

    Product came in fast

  47. Justin (verified owner)

    These plugs are amazing and definitely the best plugs you can get for your kdm vehicle. Had to wait a bit for them but that’s due to hks not kdmtuners. Kdmtuners is solid and has been great to work with.

  48. John Olszewski (verified owner)


  49. Ryan (verified owner)

    Fast shipping, thank you brap brap

  50. Delsin Toledo (verified owner)

    very good quality shipped fast

  51. Anonymous (verified owner)

    Super quick shipping!

  52. Matthew L. (verified owner)

    The plugs are working great! I contacted kdmtuners Facebook to confirm they had them in stock, they responded quickly and within a day of shipping I received my order. I’ll definitely be purchasing from kdmtuners again.

  53. Pablo Cordova (verified owner)

    Absolutely great service, quick shipping and unbeatable prices!

  54. Ivan Ng (verified owner)

    Haven’t installed so can’t give it a 5 for now.

  55. Owen (verified owner)

    Easy install, fast delivery

  56. Rafael Y. (verified owner)

    Fast shipping and just as described

  57. Sam D. (verified owner)

    The go-to plug for modifying your kia/hyundai.

  58. Sean Shepard (verified owner)

    Amazing ship times and great packaging. Nothing came damaged and every thing came super quick.

  59. kevin wilson (verified owner)

    Fast shipping and great service

  60. Carlos Tagalog (verified owner)

    As always item in perfect codition and fast delivery

  61. KEVIN AIELLO (verified owner)

    Super fast shipping. Best price. Availability. Never an issue when dealing with Josh. Great company to do buisness with.

  62. Steven (verified owner)

    better plugs

  63. Braydon Harmon (verified owner)

    Great plugs and service

  64. Mike S. (verified owner)

    Always a pleasure dealing with KDM & Josh for high quality aftermarket parts. The HKS plugs came in quickly & are great. Be sure to check and/or re-gap them to ensure they’re where you want them. [That isn’t about KDM, always check the gaps, as from factory they can vary a lot.] Kudos to KDM for excellent service.

  65. Jason S. (verified owner)

    Great product and service!

  66. Eric Austin (verified owner)

    Quick and in stock

  67. Justin B. (verified owner)

    Arrived well packaged and extremely quickly. Ordered a number of parts all at once from several different shops, and this was the first time to arrive.

  68. Brandon L. (verified owner)

    Just as expected.

  69. jason (verified owner)

    As always KDM TUNERS shipped fast, and love the HKS plugs. Great communication, fast shipping, what more can you ask for?

  70. Daryn Davis (verified owner)

    Very good product came in box with air bags protecting the product. It did take longer than expected to ship but I emailed them and got a swift response and apologized for not shipping out yet and then he over nighted them to me which I thought was really cool and made up for it not shipping out on time. And will absolutely make future purchases bc of how cool they were when I emailed them. Would also like to state that the person who emailed me was the ceo which I think is cool.

  71. Jack (verified owner)

    Great plugs highly recommend them and shipping was fast very happy with the customer service

  72. Michael Gallaspie (verified owner)

    Must have for certain applications, KDM the best prices and very helpful staff.

  73. Leo Ledezma (verified owner)

    Fast shipping like always !

  74. ERIC (verified owner)

    Fast shipping, good price!

  75. randolph A. (verified owner)

    Quick Shipping! I was very pleased with how quick I got them!

  76. Joshua M. (verified owner)

    Shipping was super fast

  77. Shawn (verified owner)

    Absolutely the best name in the KDM world.

  78. Cody K. (verified owner)

    Kdm tuners had the best price around for the HKS plugs. Shipping was fast and I got exactly what I needed. I will definitely order from them again.

  79. ALEXIS DIAZ (verified owner)

    Love them..

  80. David M. (verified owner)

    Fast shipping! The parts work as advertised. Thanks again for the available selection.

  81. kevin n. (verified owner)

    I loved the RVD6 Coupon and I was amazed at how fast it was shipped!!

    Thanks you guys!

  82. Eric Allen (verified owner)

    Best price for these plugs anywhere

  83. Anonymous (verified owner)

    They work as advertised. Great service from KDM Tuners.

  84. Sascha Wilde (verified owner)

    I’m more then happy with them

  85. Anonymous (verified owner)

    2020 Veloster N PP. Easy to install. Great customer service

  86. Kenneth (verified owner)

    Great product can’t wait to install

  87. Alex Islas (verified owner)

    Is good

  88. Alexander T. (verified owner)

    Crazy amount of protection in the packaging for this item, felt good to see the time taken to ensure the safe delivery of the product.

  89. Jason S. (verified owner)

    The factory plugs are fine but if you are going to do horsepower upgrades you need these better spark plugs. If you put on a bigger turbo you have to put these plugs in.

  90. Edwin M. (verified owner)

    Fast shipping and safely packed and secured.

  91. John Monge (verified owner)

    Very fast and excellent customer service 👌
    Thank you

  92. Cesar M. (verified owner)


  93. Carlos J. (verified owner)

    Solid plugs. So much better than what I can ever find off the shelf in stock where I live.

  94. Kevin Wilson (verified owner)

    Great guys and service was on point and fast shipping

  95. Micah T. (verified owner)

    Delivered in less than 48 hrs!!!! Runs smoother. Going to order more parts soon.

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