Has anyone heard of this?
Used it?

I just bought some from the local autozone. He said it was the best stuff in the place.

Unlike the other bottles, this one is only 2.5 ounces.

Online webpage seems convincing in their logic
www.rxp.com

 

I've used this for years in all my vehicles. Works great. I have noticed it has helped smooth out a rough idle at times. It even help my mileage at times on last pickup once it got over 50k miles or so.