These plugs utilize both Iridium and Nickel for utmost performance for street and race applications. Iridium is used as part of a 0.4mm diameter electrode core and platinum is used on the tip.

The plugs are getting excellent reviews and are still extremely difficult to locate outside of Japan. These plugs have been manufactured to be much more durable than earlier units and any rumors about problems with the tips have been squashed with the S-Series.

Please keep in mind that the plugs are available in heat ranges of 9, 10 and 10.5. If you are unfamiliar with the heat range needed we will match it with the proper range as recommended in the HKS Catalog.

We will process your order as soon as the heat range and plug type is verified.