The Saltplus Trapez Hub is a pro level, super smooth rolling cassette hub, with a Switch Drive System that lets you run the Trapez right side or left side drive. Its alloy shell & 14mm chromoly hollow axle with alloy cone nuts keeping the Trapez real tough & durable. It also features high quality sealed bearings, a 9 tooth 1-piece driver & slim low flanges. section Product Specs HUB TYPE: Cassette AXLE: 14mm Male DRIVER: 9t DRIVE SIDE: Left & Right Switchable SPOKE HOLES: 36h WEIGHT: 569g (1.25lbs)