I used this on the headlights of a 2004 Mazda that was garage kept for all but one year in California.  The headlights had surface crazing from age.  The product did nothing.  I used the Meguire's Plastic polish afterward.  I consider both a waste of money.  I could have cleaned the surface with isopropyl alcohol and used any wax.  Real disappointing given the rave reviews for this product on this site.