Moneta Farm Suppy is my Stihl dealer. They recommend using the little bottle of Stihl 2 cycle oil in 2 1/2 gallons of gas (93 non ethanol) then fill the little bottle with SeaFoam. Add to the 2 1/2 gallons. I use it in all my 2cycle machines. Works great. Good start ups even after long layovers.