For drivers that care about performance.

By using a 0.4mm diameter iridium alloy center electrode and a special ground electrode, IRIDIUM POWER realizes spark performance unseen until now. It steadily gives a high level of response under a variety of driving conditions. The result? Increased acceleration and torque compared to regular plugs.

For drivers that care about mileage.

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

Built-in, Highly Reliable Resistor

All IRIDIUM POWER plugs include a highly reliable, 5,000 ohm monolithic resistor specification to reduce electromagnetic noise that may affect electronic devices. (For all plug types)

Highly Corrosion Resistant, Burnished Nickel Plating

The plug housing is plated with burnished nickel, the same as plugs used for racing. It is highly resistant to corrosion and rust even while touring in continually rainy weather and during motocross events. (Low-heat range types excluded)

360° Laser Welding

The process used to mount the iridium tip is a highly reliable “All-around Laser Welding” process that is able to withstand all kinds of driving conditions. (For all plug types)Projected Center Electrode

In order to improve ignitability, the center electrode protrudes more than with conventional type plugs. This improves both acceleration response time and performance.(Only with: IU31, IUH24, IUH27, IX22, IX24, IX27, IUF22, IUF24, IWF22, IWF24, IWF27, IW24, IW27, IW29, IW31, and IW34)0.4 mm Diameter Ultra-fine Iridium Center Electrode

Using a new iridium alloy with a very high melting point, the tip of the electrode can be made very fine. This enables the reduction of voltage necessary to cause the spark, and greatly improves ignitability. Moreover, the special iridium alloy used was developed by DENSO

Taper-cut Ground Electrode

The tip of the ground electrode is cut to a fine taper to reduce the adverse effects of quenching, which greatly improves fuel ignitability. Also, because of the streamlined, taper-cut shape, the fuel-air mixture spreads more evenly in the gap, resulting in steady, reliable igniting of combustion.(excluding IUF27A, IUF31A, IU24A, IU27A, IU31A, IY24, IY27 & IY31)

U-Groove Ground Electrode

The U-shaped groove on the ground electrode insures that the inside surface area is large enough to generate the flame kernel. This shape enables lower voltage needed to cause the spark and results in excellent ignitability without increasing the size of the spark gap. (excluding IUF27A, IUF31A, IU24A and IU31A)

Insulator Projection

The projection of the insulator is optimally designed based on each plug's thermal value. This corresponds to requirements unique to thermal value, such as self-cleaning ability at lower thermal values, and heat resistance at higher thermal values. (For all plug types)