The STIHL round file with guide plate Ø 3.2 mm is designed for sharpening or adjusting chains with a 1/4" Picco pitch. The guide plate includes special markings to help set the correct sharpening angles for the chain’s cutting tooth. When the file wears out, it can be quickly and easily replaced. Regular sharpening keeps your cutting chain maximally sharp, making work easier and reducing strain on the tool itself.