Strengthening and Nourishing – Our Difeel Rosemary Mint Hair Mask is infused with nourishing Biotin. Biotin plays an important role in the health of your hair, skin, and nails. A lack of Biotin can lead to hair loss. For Stronger, Fuller and Thicker Hair – Our Strengthening formula leaves hair stronger, fuller, and thicker while encouraging healthy hair growth. Our Rosemary and Mint Hair Mask works to keep your hair color vibrant while giving your hair manageability, softness and shine.