When used with the Pro Longer shampoo, there is a 47% hair breakage reduction and split ends are reduced visibly by 41%*. The Filler A-100 technology is patented to L'Oreal Professionnel, and it works by penetrating the fiber core to plump and thicken the hair from the inside. Amino acids in the formula work to strengthen the hair from the outside. The formula works on thin ends, or areas where help is most needed. Instantly fills ends. Visibly reduces spilt ends. Thicker and shinier hair.

How to use: Apply to shampooed, towel-dried hair. Do not rinse. Blow-dry or straighten as usual. 

*instrumental test, after application of Shampoo + leave-on. With the Serie Expert Pro Longer Multi-benefit leave in treatment: 47% less hair fall due to breakage*, 41% split ends reduction** *Instrumental test **Instrumental test Pro Longer Lengths Renewing Shampoo + leave-on