Alright well I have done my research and reached out to NGK directly with no response or concrete answers so I figured I would ask you guys. I purchased 2315 iridiums for my car from rock auto. I pulled the old plugs and compared them closely to the new ones. All looked fine till I noticed the logo on the new plugs do not have the horizontal line under the P of Japan like my old ones do. So curiousity got the best of me and I scrounged up every single ngk plug I could find around my shop and ALL of them had it. Should I be worried I got duped? I’m honestly to paranoid at this point to install them. Please help and thanks.