The large size vent for medium to long hair. The crescent moon design of the vent brush allows for maximum airflow and circulation; this speeds drying time. The heat- resistant, ball-tipped, nylon bristles are extremely flexible; they grip and shape the hair into whatever configuration you desire. They're designed to be flexible and extremely comfortable to the scalp. The curvature of the side base and the crescent moon bristle pattern allow you to get close to the scalp, thereby creating maximum lift, volume and fullness. The crescent moon bristle pattern flows through the hair easily, separating individual hair strands smoothly. Strands never tangle, allowing you to work quickly and efficiently on wet or dry hair.