Mag 1, 12 OZ, Fuel Injection Cleaner, Formulated With Jet Fuel, Keeps Injectors Clean, Reduces Friction, Use With Every Tank, Outstanding Cleaning Power, Fights Power Loss & Restores Performance, Smooth's Rough Idle & Improves Drivability, Protects Against Valve Stem & Seat Wear At Intake Valves, 1 Will Treat Up To 21 Gallons Of Fuel.