The cost was 14. 20 Including tax and you send It to Oil Analysis Laboratory P. O. Box 105322 Atlanta, Ga. 30340 Phone 770 454 8000 I went to the Napa store and ask about this and they said no problem so now I am going to take a sample of my oil and send It IN. There Is a form to fill out In the first bottle and a bottle to put the oil In and then send It. :-laf