[69heavychevy]

A little back story first, so you can learn from my mistakes:

My two Nissans needed plugs replaced since they reached 100k miles. Went to my local O'Reilly's to price some OEM plugs (NGK double plat.). $10 a pop, ouch! I needed 12 of them (V8 and I4). I personally run NGK plugs on anything and everything I can, yes even on my square. Its a very high quality plug and its one that has never given me any issues.

After a few minutes of searching on Ebay and making an offer, I had 12 plugs being shipped to me for $83! What a deal I thought.
A few days later plugs arrived, I give them a once over. They looked good, or in other words nice and shiny.

A couple weeks later I finally get around to installing them...as I'm removing the old plugs and comparing them to the new plugs I noticed a couple subtle differences, but I really didn't give them much thought.

As I finally get around to installing the final plug I noticed that the build quality of this particular plug looks terrible...that should've been a red flag...but I was too proud of myself for having saved $50, so on it went.
I go to start up my vehicles and they crank a little longer than usual, uh oh! They both start to run rough, but smooth out after about 10 seconds...double uh oh!

I drive them around the block and everything seems to be running fine now. I convince myself I was just overreacting...

After a couple of days, I'm still thinking about that last sorry looking spark plug I installed...I start to wonder if there's even such a thing as counterfeit spark plugs...I decide to do a quick Google search...triple uh oh!! and an AAAAHHHHH SHHHHIIII......

I find that NGK plugs are one of the most commonly counterfeited spark plugs.
I run to O'reilly's and buy a set from them and pull the set of plugs I installed and do a comparison...this is what I found....
BTW NGK has an article on their website on how to spot counterfeit plugs.