The Definitive Cassette is the most advanced hub that Shadow has produced to date. With 120 points of engagement, the Definitive Cassette features a 3 pawl engagement system that uses 4 notches on each pawl for almost instant power transfer. The sleek and low-profile hub shell is CNCd from 6061-T6 alloy, with precision bearings, 7075 hardware, and printed logos. Low drag, high engagement with minimal pedal gap and it sounds like a hive buzzing bee!