Take 2.1 gallons (easy to read on the pump) of gasoline and add it to a gas can that already has 6.4 ounces of fuel-mix oil in it and nothing else. The result is 42 to 1. Several of my older saws have run on this mixture for over 20 years and the newer ones like it also. Just remember to add the oil to the empty gas can before you head to the filling station.