L'Oréal Professionnel Serioxyl Advanced Hair Thickening Serum is a volumizing serum that improves stress-induced hair loss in 12 weeks. The advanced formula of L'Oréal Professionnel Serioxyl Advanced Hair Thickening Serum revitalizes thinning hair from the roots, effectively supporting follicle regeneration, contributing to stimulating hair growth and restoring hair density.