Check the listing for details. HAPCO - Fuel System Cleaner - WORKS IN ANY FUEL SYSTEM - 2 PACK. Condition: New. Listed at 54.98 USD. Fuel System Cleaner - 2 PACKUse to thoroughly clean and lubricate any fuel systemFormulated to improve performance, reduce fuel emissions, stabilize fuel, remove harmful deposits and prevent future carbon buildupHelps eliminate knock, ping, run-on and start difficultiesSafe to use in all gasoline, diesel and marine enginesOne bottle treats up to 25 gallonsHapco Fuel System Cleaner is guaranteed to thoroughly clean and lubricate any fuel system. Formulated to improve performance, reduce fuel emissions, stabilize fuel, remove harmful deposits and prevent future carbon buildup. Contains a blend of cleaning and lubricating agents that help eliminate knock, ping, run-on and start difficulties. Will not harm oxygen sensor or catalytic converter. For Best Results: Add one 16 oz. bottle of Fuel System Cleaner directly to fuel tank. One bottle treats up to 25 gallons. Repeat as necessary (average of 3000 miles). Safe for all gasoline, diesel and marine engines. Size - 16 oz. - 2 Pack Part No. - 3716P2 Made In USA - Money Back Guarantee - Proven Results Since 1960 Visit HapcoProducts.com to learn more!