15% lighter and stiffer than the previous model . Now featuring a self-extracting axle-to-arm interface, simplifying fitting and removal . Forged and CNC machined 7075 series aluminum alloy crank arms. Unique expanding spline/arm interface. Versatile spline mount for chainring/spider. 30mm oversized axle. Weight: 641g (arms, axle and 34 tooth spiderless ring)