Fits 28" Stihl Chainsaw models 066, MS500i, MS660 & MS661 using a 91 drive link chain. Oregon Part Number 75EXL091E / 75EXL091 / 75EXLO91 / 75EXLO91E. Standard Sequence chain. Designed to require less force from the operator to get through the cut quickly, Oregon PowerCut™ 70-Series EXL makes the job feel like less work.
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