All new Whistler Pro Front Hub. Clean and simple looks with the male into female axle system. 36H low flange aluminum hub shell with a 4140, 14mm heat treated CRMO center axle, 3/8� bolts that are longer than previous or traditional for added strength when running pegs and 2 large sealed Japanese bearings that are pressed further into shell to prevent bearing blowouts and movement. This hub also includes both press on plastic hub guards to keep those spokes safe.