3D smart volume hot brush that gives 2x more volume* from root lift to added body through the lengths A smart hot brush for quick and effortless, three-dimensional volume that lifts your roots and creates body through your lengths. The brush‘s heater technology spans the one and one-quarter inch barrel, responding to your hair‘s needs and ensuring a constant optimum temperature of 365°F to achieve healthy, long-lasting volume* with no extreme heat. Smooth, half-centimeter nylon bristles are developed at the optimum length to create gentle styling tension, allowing close contact with the roots for maximum lift and smooth gliding through hair for tangle-free styling.