The D4 is recommended for longer hair length. The D4 is perefect for blowdrying hair straight. The extra rows of bristle provide additional control and tension to the hair. For smoothing fine to medium hair Smooth nylon bristles grip & control the style Use with a blowdryer to straighten natural movement Available in 3 sizes - with 5, 7 or 9 rows of bristle The more rows of bristles, the better the grip What makes a Classic Styling Brush? All the Classic Stylers are characterised by smooth, firm nylon bristles embedded in a pure rubber base. The nylon bristles are rounded at the ends, so do not scratch the hair or scalp. The rubber base is semi-circular in shape and this becomes more defined in the larger sizes. During blowdrying, you can rotate the brush through the ends of the hair, adding slight curl and bend.The Classic stylers are heat resistant, so they can be used with a blowdryer. They can easily cleaned in soap and water.