Thanks to their multiple properties, the boar bristles of the Universal Hair Brush deeply nourish your hair. Since they are full of keratin, they provide your hair with natural hydration, drawing sebum from its roots and distributing it evenly throughout your hair. Your hair benefits from continuous and natural shine. Thanks to their multiple properties, the boar bristles of the Universal Hair Brush deeply nourish your hair. Since they are full of keratin, they provide your hair with natural hydration, drawing sebum from its roots and distributing it evenly throughout your hair. Your hair benefits from continuous and natural shine.