TRESEMMÉ Hydra Matrix Hair Serum is a lightweight, water-based leave-in conditioner enriched with Polyglutamic Acid (PGA) to deliver intense hydration, control frizz, and protect hair from heat styling. It helps lock in moisture for up to 100 hours, leaving hair soft, smooth, shiny, and manageable without feeling greasy or heavy. Suitable for all hair types, including straight, wavy, and curly hair.