Made by Nippondenso. I only buy MP ones thru Mancini.. At least I know they work. Remans are cheaper, but I have heard them fail. Chinese ones are cheaper, but again, I know I never have a failure, so I wont compromise. Another good source are wrecking yards for anything froma Magnum V6 or V8. I have installed over 10 MP ones, 4 on my own stuff. No failures, even from my 9yr old one on my truck. Best single part MP ever sold IMO....lol.