Pferd made several products for Stihl, including the hexa file. Pferd at edge dressing tool is the best and most accurate way to remove the burr that builds up on the edge of your guide bars. Designed to hold the reversible file parallel to the bar face, you only remove the burr, and take away the risk of tapering the top rail when using a hand file, thus narrowing of the edge increases the wear rate.
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