The new Federal Motion freecoaster hub features a completely new axle along with a nylon clutch retention spring. By replacing the traditional spring/ball system, the new hub requires less maintenance & is a lot easier to disassemble. The nylon retention spring also reduces the internal drag & enables faster rolling & smoother crankflips section Product Specs HUB TYPE: Freecoaster AXLE: 14mm Male DRIVER: 9t SPOKE HOLES: 36h WEIGHT: 669g / 23.6oz