Concentrated tetraethyl lead substitute formulated to increase the octane rating of gasoline up to 10 numbers or more. Helps eliminate engine damaging detonation, spark knock, pre-ignition and pinging from low-octane gasoline. Modifies the burn speed and flash point of gasoline to create a stable combustion chamber flame front, maximizing performance and power. Stabilizes oxygenated gasoline to prevent lean-out conditions. Provides needed upper-cylinder lubrication that is missing in unleaded gasoline. Not alcohol-compatible. Made in the USA.