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For long distance and heavy-use drivers.

By greatly minimizing electrode wear, DENSO improved mileage and extended the plug’s useful life. Longevity provides you with peace of mind and safety when using IRIDIUM TOUGH.

For drivers that care about mileage.

If you use your car on a daily basis, you may be concerned about fuel consumption.
IRIDIUM TOUGH is one solution.


360° Laser Welding

The iridium tip is mounted with an “All-around Laser Welding” method that insures high reliability and durability even under the most severe driving conditions.

Highly Corrosion Resistant, Burnished Nickel Plating

The insulator housing is plated with burnished nickel the same as racing plugs, resulting in high corrosion resistance. (VKA and VKB excluded)

Built-in, Highly Reliable Resistor

All specification types include an embedded, highly reliable, monolithic resistor to eliminate electromagnetic noise interference from all kinds of electronic devices.

Platinum-tipped Ground Electrode

The ground electrode has a platinum tip, from DENSO’s experience with platinum plugs. This moderates electrode wear and insures high durability.

Fine Diameter Ultra-fine Iridium Center Electrode

Using DENSO’s iridium alloy having a very high melting point, the tip of the center electrode can be shaped very thin and fine, reducing spark voltage requirements and greatly improving ignitability.

High Durability


Improved Mileage

Improved Ignitability

Realizing high ignition performance with a fine diameter electrode.


Improved Acceleration

Stable ignitability improves acceleration


Actual products may differ from images shown.