OK, this may seem a little naive, but its never occured to me until now. Is two stroke oil all the same? I have a Craftsman chain saw that uses a 40:1 mix and a Stihl edger that uses a 50:1 mix. I've run out of the 2.6 oz. oil containers that I've been using in my old 50:1 edger/trimmer. I have Craftsman two stroke oil in 3.2 oz. containers and it states that its for 40:1 mix. Is the Craftsman oil just labelled for 40:1 because of the amount in the container and it would be safe to use it in the proper ratio of 2.6 oz. per gallon in my Stihl edger? If so I can just dump 3.2 oz of the Craftsman oil into 1.25 gallons of gas. I rarely use my chainsaw and figured I might as well use up the oil I have for it before buying more if I can.