Delivering up to two weeks of flyaway control, the L'Oréal Professionnel Keratin Alpha Sleek Hair Serum encourages glass-like shine and ultra-sleek results. The leave-in treatment helps to protect against the effects of humidity and thermal damage up to 230°C. A 5% Keratin Sealer complex encourages a fuller, healthier look, while promising up to five days of mirror-shine and smoothness. Saturate strands with the lightweight, heat-activated spray and blow dry, then flat iron for optimal results. Results: Up to 2 weeks of frizz control* Up to 5x smoother hair and 2x less frizz** Controls unwanted volume for daily styling in half the time*** Delivers instant shine that lasts up to 5 days.**** The serum helps to fight against up to 80% humidity***** Heat protection up to 230°C (450°F)****** *Instrumental test after 4 uses of Smooth Transformer. **Instrumental tests with routine 4 times of Shampoo + Smooth Transformer + Leave-on. ***Consumer test on 68 participants, 1 application/week for 4 weeks. Based on a 15-day break observation. ****Instrumental test after 1 application of shampoo, mask & serum. *****Instrumental tests, with full routine after 4 uses of the Smooth Transformer. ******Instrumental tests.