Unleaded gasoline antiknock additive mainly composed of methylcyclopentadienyl manganese tricarbonyl (mmt) and a small quantity of stabilizer and dispersant. It is used in the gasoline blended mainly and boost the octane number of gasoline efficiently. Packed in 200 l zinc iron plating pail, net weight 200 kg/pail, or packed in specially made storage tan, 5 t, 10 t per tank or as required