DENSO's proprietary iridium alloy is extremely hard and wear resistant. This makes it possible to produce a spark plug with a center electrode of just 0.4 mm, which produces a more intense spark and better ignition performance under all driving conditions. These spark plugs can withstand even the most severe conditions, and have proven themselves in original equipment and competition. This product secures DENSO the leading position in the field of iridium spark plug technology.