L'Oréal Professionnel's Pro Longer concentrate treatment thickens long hair for visibly healthier and stronger looking lengths. ​When used with the Pro Longer shampoo and ends-filler treatment for long hair, split ends are reduced visibly by 66%.*​The unique Filler A-100 technology 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.​

*Instrumental test, after application of Shampoo + mask + concentrate

How To

Once a week, replace your conditioner/masque with the single dose concentrate. Apply the single dose concentrate on towel-dried ends. Twist ends for better penetration. Leave in for 5 minutes. Rinse out