A high performance chainset from the trekking group, using the most advanced 10-speed Dyna-Sys chainrings Forged Hollow Tech II aluminium cranks offer unrivalled strength-to-weight ratio Lightweight construction with external super smooth bottom bracket bearings for efficient use 48-36-26T chainring combination HG-X chainring with patented spike pins give smooth & fast gear shifts under load Stiffness & strength increased with advanced design due to wider spaced bearings & oversized axle For use with 10-speed HG-X MTB chains only We recommend that this bottom bracket is initially installed by a bike shop to ensure perfect bottom bracket facing & fit 50 mm triple ring chain line for use in conjunction with 135 / 142 mm O.L.D.