CenterLine 2-piece rotors are the lighter-weight version of SRAMs quiet, smooth and robust CenterLine rotorsCenterLine venting reduces vibrations by providing consistent friction levels throughout the rotation2-piece design offers reduced weight as well as improved heat shedding abilities Rounded edges make for easier wheel installs and are UCI-compliant.Available in 6 Bolt and CenterLock configurationsAluminum body with steel braking surface6-Bolt version features steel bolts140mmSilver/BlackCenterline6BUPC/EAN/GTIN: 710845805547