Biolage Professional SmoothProof Deep Smoothening Hair Serum is a salon-inspired anti-frizz serum designed to deliver long-lasting smoothness and shine. Infused with nourishing avocado oil, this lightweight, non-greasy formula helps control frizz for up to 72 hours, even in high humidity. It leaves hair up to 6x smoother and shinier while improving manageability and softness. Ideal for frizzy, dry, and unmanageable hair, this professional hair smoothing serum protects against humidity, enhances gloss, and keeps hair silky-smooth, making it a high-search choice for frizz control and deep hair smoothening.