Eco-Friendly Birchwood and Cork Boar Bristle Round Hair Brush Creative Pro Hair Tools eco-friendly boar’s hair round brush is made with birchwood, cork and boar bristle — all are sustainable materials! The ergonomic cork handle provides a non-slip grip that limits stress on hands and shoulders while you style and the boar bristle stimulates the scalp's production of natural oils, leading to a polished, shiny blow out. Enjoy a beautiful blowout naturally and comfortably with a cork boar bristle round hair brush that you can feel good about using every time you style your hair!