Knob on the embroidery machine that allows the sewing speed to be adjusted up or down. On most modern embroidery machines, the speed at which the pattern is stitched varies according to the length of the stitch. Shorter stitches are made at higher SPM and longer stitches are made at slower SPM. This is necessary due to limitations of the movement of the pantograph and is also determined by the number of heads and/or hoops being driven by the machine.