S-AQUA Roll Brush, 43mm. New and unused. Please refrain from purchasing if you are sensitive to items that have been handled by others. Product Description: Science Aqua Roll Brush 43mm. Ideal for blow-drying and finishing treatments. This roll brush prevents hair from snagging and changes color when heated to indicate the appropriate temperature. The stainless steel part turns white when heated to over 60 degrees Celsius with a hairdryer, allowing you to check the temperature.