Professional heat-activated smoothing serum for anyone with unruly hair looking for a product that smooths and provides long-lasting protection against frizz. After use, apply a hair dryer or any hot styling tool. Helps control frizz for up to 96 hours, even at 97% humidity!* Smooth hair effect for up to 5 washes** Heat protection up to 230°C*** Suitable for all hair types and textures. *Instrumental test after application of shampoo, mask and serum from Mega Sleek range. **Consumer test, 57 participants ***Instrumental test on Mega Sleek Serum.