The Definitive Cassette is the most advanced hub that Shadow has produced to date120 points of engagement and a 3 pawl engagement system that uses 4 notches on each pawl for an almost instant power transferMicro-notched pawls with individual leaf springs6061 alloy hub body w/ 2 precision sealed bearings1pc 9T chromoly driver w/ 3 precision sealed bearings14mm hollow chromoly axleRR1s w9t Driver36HB/O 14mmAlyPur498gRIM110UPC/EAN/GTIN: 810034520937