The Brother Dual Function Fold Binder is a versatile accessory used to fold 1.25-inch (32mm) wide bias fabric tape into 0.31-inch (8mm) wide double fold bias tape, then apply the binding to the edge of fabric. It easily attaches to the cover stitch machine with the two included screws. Additionally, this binder can also be used for single fold bias tape, making it an essential tool for achieving clean, professional finishes on a variety of sewing projects.