Difficult-to-work-with fabrics are best sewn using the Walking foot. It supports the fabric feed by adding a second feed dog on the upper side of the foot. The project is then evenly moved simultaneously top and bottom by the two feed dogs for a smooth sewing process. A walking foot is ideal for thick projects such as quilts, as well as slippery materials such as silk or plastic. For the bernette 37 or 38 models.