This 205 firm iron on interfacing is ideal for medium to heavier cotton and cotton blends giving it a firm handle. Also suitable for waistbands and skirt collars. Place the Interfacing with the coated side on the wrong side of the fabric. Cover the entire area with a damp ironing cloth. Press each area for about 10 to 12 seconds, being careful not to move the iron. Iron setting: Wool/cotton. Allow the pieces to cool flat for about 30 minutes, so that it can set properly. It is strongly recommend that you attach a small piece of interfacing to a fabric remnant with your iron first to make sure that the hold and the adhesion meet your expectations.