Stihl MS150,MS150T,MS151,MS151T,MSA120,MSA140,MSA160 - don't worry as you already have a 1/4 drive sprocket on these saws. The original 1/4. 043 picco chain was the Stihl 3670-71PM3 and this chain was ground breaking in it being the smoothest, thinnest and cleanest cutting chain on the market.
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