What is it: A glossy, lightweight serum that shields against damage caused by heat styling. Who is it for Perfect for all hair types, especially those in need of heat protection and moisture. Why is it Special. If you're going to bring the heat, be sure to use protection. This hair serum is an absolute must-have for combatting the damaging effects of heat tools and blow drying up to 450 degrees. Just a few drops helps to prevent against moisture loss, banishes frizz, and adds healthy-looking shine.