Extruded and CNC-machined from 6061-T6 aluminum, BOX hub spacers feature a minimalist design that is super lightweight and extremely good looking. Weights range from 0.2 to 0.8 grams, depending on the size. Sold in packs of four, including two 1-millimeter and one each 3- and 5-millimeter widths, a set provides spacing adjustments from 1 to 10 millimeters.