Fine Wire reduces the amount of voltage required by the ignition to fire a spark. That's why the smaller the center electrode the better performance you achieve. Denso Iridium is by far the smallest electrode on the planet at .04mm, than NGK Iridium at .07mm and so on.
I gapped my plugs at .054...
I'd like to mention that I have the AWSF22FS and it sure don't look to me to have a platinum cap on the ground side and I know I got the part# right, I'm looking at the box as I'm righting this. I could be wrong by as viewed by my naked eyes I didn't see any platinum on ground though I sure hope that's not the case and my eyes we're just deceiving me
