I hope this is not a stuped quetion. but if it is then I gess that is just the way it is. lol


I got a spark plug with my ignition. It is a NGK BPMR6F. On the box is has a big X on a pic of a air plane. Now This came with my cdi ignition so I know that it is good plug for the ignition but I would like to know why is there a X and a pic of a plane?

Can some one give me some info on this plug..
thanks
Paul