Stiffen is an extremely stiff material that bonds to other fabrics creating a rigid material similar to cardboard. It is made from polyester. Stiffen is perfect for making totes, bags, purses, table top decor, boxes, costumes, hats, and any other project that needs a stiff backing. For best results, place the rough adhesive side of stiffen on the back of your fabric. Then use a damp cotton setting cloth, and with a steam iron set to cotton or linen setting, apply pressure, heat and steam for 20 to 30 seconds. Stiffen comes in 20" wide by 10 yard roll.