Description L'Oreal Professionnel Pro Longer Mask Extremely long hair is strengthened and protected by L'Oreal Pro Longer mask. Because A-100 filling technology fills in the ends to promote healthy hair growth, the regenerating mask ensures healthy strands. Hair looks healthier, fuller, and stronger. For fine-tipped hair, L'Oreal Serie Expert Pro Longer is the ideal treatment to fill in the ends and give them strength and shine. Application method Distribute equally across towel-dried, clean hair. Rinse well after leaving on for three to five minutes.