Revlon One-Step Hair Dryer & Volumizer Over 2,400 buyers have reviewed this Revlon One-Step Hair Dryer & Volumizer ($36), and 73 percent of those people give it a perfect five stars. What makes this tool unique is that it's a brush and blow dryer in one product. The oval brush is designed for smoothing the hair, while the round edges create volume. Image Source: amazon.com Revlon One-Step Hair Dryer & Volumizer $36 from amazon.com Buy Now