Olaplex Nº.9 Bond Protector Nourishing Hair Serum is an ultra-lightweight, leave-in formula that shields hair from pollution for up to 48 hours while providing heat protection up to 450°F. Infused with Olaplex Bond Building Technology and antioxidant-rich Red Algae, it forms an invisible barrier to block pollutants, neutralize free radicals, and prevent damage. This expert-designed serum enhances shine, softness, and frizz control while improving style retention and reducing tangles and static. Vegan and Cruelty-free Gluten-free and Nut-free Paraben-free, Sulfate-free, Phthalate-free, Phosphate-free and Silicone-free Free of DEA, Aldehydes and Formaldehydes Who is it for? All Hair types What does it do? Protects against heat and pollution Reduces frizz and flyaways Add shine and softness Protects against heat up to 450°F/232°C Restores the hairs appearance and texture How do you use it? Apply a small amount to clean, damp hair working upward from ends to roots Use more as needed for longer, thicker hair Style as usual Air-dry for a soft texture  Blow-dry for a smooth finish Diffuse for defined waves or curls