I calculated my savings.
My tank holds approximately 15 gallons. At 20 miles per gallon on an average provides me 300 miles.
If I can save 18% that will allow me 354 miles per tank.
54 miles is approximately 2.7 gallons at about $3.50 a gallon I save $9.45.
If I fill my tank up twice a month, I am saving $18.90 less the costs of the pill that is approximately $3.00 each; that would be a net savings of $12.90 a month ($154.80 a year).
This is affiliate marketing so I will make money when other people want to save anywhere from 5% to 18% or higher in some cases.