Our Beard Care Serum Set Contains Mineral Oil and Hydrogenated Castor Oil; Roller: Stainless Steel. It Can Promote Beard Growth and Make You Have a Thicker and Healthier Beard. Its Usage Is Very Simple: 1. Clean and Dry Your Beard, 2. Gently Roll the Dough with Rolling Pin and Massage the Place Where the Beard Grows. 3. Then Take Appropriate Amount of Essence and Apply It Evenly on the Skin. 4. Use It 2-3 Times a Week for Better Effect. And the Ingredients That Can Promote Hair Growth Are Conducive to Increasing the Density and Length of Beard Hair.