Disappearing chalk. Excellet for drawing on fabrics and knitted fabrics. Perfect for the most delicate fabrics. Used for marking place of sewing-on pocket, flap etc. It does not leave the traces and spots. The marks disappear themselves after about 2 days or immediately under steam iron's influence. Disappearing time may vary with fabric's type and surroundings conditions such as temperature, humidity and air circulation. Useless marks can be easily remove by brush.