This Pro Ultra Ceramic Thermal Hair Brush is constructed using materials that retain heat in the core of the brush, which makes it easier to style the hair when blow-drying. Pro ultra ceramic thermal round hair brush eliminates frizz and emits negative ions that break down bacteria build-up. The heat-resistant bristle reduces static and seals the hair cuticle, limiting the damaging effects of excessive blow-drying. One-piece, glue-free design with no snagging neck ring and a rubberized handle. Choose from a variety of sizes. Please note: all our round hair brushes are measured by the diameter of their bristles, not barrel size.