Prolong is a line of oil additive, spray, gas additive and a few other things. They have an infomeshal on this and one of the things they show you is a car running with NO OIL in it. They did use the Prolong additive though. I run it in my wife's Honda, but don't really see a difference. Hard to say though... You can get it in some parts houses these days.
BTW, I found this link about the FTC and Prolong Inc.
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