If you want to look my best and give my best to your bike then you have to choose IRIDIUM POWER DENSO's patented iridium alloy is extremely hard and wear resistant. This makes possible the production of a spark plug with a central electrode of only 0.4 mm, which produces a spark more intense and the best ignition performance in any driving conditions. These plugs can withstand even the most severe conditions, and have proven themselves in original equipment and racing. This product gives DENSO the leading position in iridium spark plug technology. The result? Increased acceleration and torque, but also last longer.