Kerastase Première Serum Filler Fondamental is a lightweight leave-in treatment for the inner repair of all types of damaged hair, leaving it glossy and supple. 

This dual-action serum has a dual action: it's light, balmy texture seals the cuticles to shields hair's surface, while filling the fibre and reinforcing hair strength. Hair is protected from calcium damage of hair water, as well as humidity and heat up to 230°C. Frizz is eliminated and hair is left smooth and supple, easy to style.