... damaged & sensitized hair The exclusivesalon ESSENTIAL STRAIGTENING CREAM is a professional, permanent hair straightening system that transforms curly or wavy ... 45 minutes maximumVery Resistant hair: 60minutes maximumIRON OPERATION PRECAUTIONS:A>,To prevent damage to hair, it is recommended to ... is left in the hair, the heat of the iron will generate steam, which could cause irritation to the skin. ...