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    Denso Iridium Long Life Spark Plug

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    Warranty Information
    This item is not eligible for further promotional discounts, coupons or special offers.
    Save $15 By Mail when you buy 4 or more Autolite Iridium XP or Iridium Ultra spark plugs and a FRAM Air Filter. See rebates page for more details.
    Save $15 By Mail when you buy 4 or more Autolite Iridium XP or Iridium Ultra spark plugs and a FRAM Air Filter.
    • Product Details

      Part No. F1000398006ND

      Warranty Details (1 YR REPLACEMENT IF DEFECTIVE)

      The DENSO Iridium Long Life spark plug was specifically designed for long service life and consistent performance in the latest, most advanced production cars DENSO's patented iridium alloy is more durable than even platinum, allowing the center electrode to be shrunk to only 0.7mm in diameter. This produces a dramatic improvement in ignitability and spark plug life. Closely related to platinum and exhibiting even tougher qualities, the rare metal iridium is an ideal material for spark plugs. A fine-wire, 0.7mm iridium center electrode is 360-degree laser welded in place using an exclusive DENSO process, and then matched to a platinum ground electrode. This pair of precision-formed, premium-metal electrodes dramatically extends the plug's useful life.

      Product Features:

      • Fine-wire iridium center electrode
      • Platinum ground electrode
      • 360 degree laser-welded spark tip
      • Sustained spark performance over 100,000 miles
      • Withstands higher pressures and temperatures
      • Reduced spark plug wear and erosion The DENSO Iridium Long Life plug has been selected as original equipment on many of the world's top cars, including those from GM, Toyota, Honda, and Mitsubishi. There's a simple reason for that: these manufacturers needed the best.

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