Gunk MAS6 Mass Air Flow Sensor Cleaner - 6 oz. GUNK is a local family owned company based out of Charlotte, NC. For more than 75 years, GUNK products, developed by the people who use them, has earned the trust of hard-working tradesment and the active DIYer through consistent, superior performance and a commitment to innovation. Improves performance and fuel economy Dissolves dirt, grease and flux Helps restore engine performance Helps reduce rough idles