There is more to the carbon headsets than their exceptional good looks. From top to bottom, Box One Carbon Headsets have been designed to perform. Each unit features a custom CNC-machined alloy top cap in the shape of the Box logo with cutouts to reduce weight. At the centre of the top cap is an anodised aluminium bolt that threads into a gold anodised aluminium expander plug. This expander eliminates the need for a star nut.