Extensively weight-optimized, almost every visible crank surface is CNC machined from a burly forged blank. The design leverages the modular spindle system of e*thirteen's carbon cranks with alloy arms that peak the strength-to-weight ratio scales. They come with custom molded crank boots for added impact resistance, an alloy extractor bolt system, and APS Adjuster. Compatible with Helix flip-flop chainrings, they can adapt to both Boost or Super Boost chainlines.Features:Forged, CNC machined alloy crank arms and 30mm AL 7050-T7 spindle for Down-Country weight with Enduro strengthCompatible with Helix Direct Mount Chainrings for Boost/Superboost ChainlineSelf Extracting Bolt System, and APS Adjuster for ease of installation and serviceProven creak-free Quick Connect ring interfaceMolded crank strike boots and thick, clear polymer protective decalsAvailable in shorter arm lengths, starting at 160mm.