These are a high quality anodized aluminum brake hub made in Italy. The design of this hub makes it very light weight. Rotating weight is the worst kind of weight on a kart. We offer them in many sizes and colors. This hub fits on many European made karts. This hub has 6 mounting holes that are 58mm apart. To see if this will fit on your kart just measure your current brake hub from the center of one bolt to the center of the next.