Biolage Full Rescue Densifying Leave-In Spray is a lightweight formula designed to boost hair fullness while nourishing the scalp. Infused with rosemary oil and niacinamide, it instantly enhances the appearance and texture of thicker hair, smooths flyaways, and detangles for effortless styling. After just one use, hair feels softer, looks fuller, and becomes easier to manage, making it an ideal finishing step in the Full Rescue routine—especially for fine or thinning hair.