The SL-K Light uses uni-directional carbon fibre strands. This gives it the same type of finish as the original SL-K, but with a weight savings not dissimilar to the K-Force Light.
The main benefits of the hollow carbon construction are simple: Stiffness and weight savings. You'll also feel zero crank flex, even on the 110mm BCD version. Fitted to the arms are a pair of Semi solid AL7075 100% CNC process chainrings secured by AL7075 Torx T-30 alloy chainring bolts. Crank arm weight is decreased by 120g in comparison to the 1st generation SL-K too. Unlike the K-Force Light, the SL-K Light uses glass fiber content to help reduce manufacturing cost. Thanks to this, you get serious weight savings and serious cost savings.
The SL-K uses a Mega-Exo bottom bracket which is built with hardened steel ball bearings instead of the ceramic hybrid bearings of the K-Force Light, this helps reduce the cost of the overall system but allows for an upgrade to the Ceramic version at a later date. Q-factor remains narrow at 147mm and a chainline of 43.5mm ensures smooth shifting with 9 or 10 speed Sram, Shimano or Campagnolo drivetrains.