This knit foot is a unique foot that allows you to sew on knit fabrics without stretching the fabric as you sew it. It prevents the puckering of the fabric and the skipping of stitching, which can occur by using a regular sewing foot. It has a little piece on the foot that can hold a piece of fabric tighter against the sewing machine as the needle goes through the fabric. This small piece helps to keep the fabric from puckering. It can be used with sheer knits all the way to heavier knits.