What is the stitch length dial setting used for sewing buttons?

Set the stitch length dial to '0' when sewing a button, as this setting means material is not fed. The numbers on the dial represent the stitch length in millimeters, and the higher the number, the longer the stitch. The 'F' to '1' range is for making a satin stitch (closed zigzag), used for buttonholes and decorative stitches.