I don't see any stamping on the metal hex. Besides the Chinese will clone anything of value.
Have any of you disassemble one these plugs? I have taken the plugs apart and the NGKs are actually mark on the porcelain where you would not normally see it., down inside the metal mounting hex. I found this when I was making myself some pressure/vacuum adapters for testing 2 cycle crankcases. I also took one CMR6A apart to find why it was shorted when in use. I found a defect in the insulating porcelain inside the metal shell.
But personally I avoid nearly anything that are clones due to all the problems I had with them.
