Replacement derailleur hanger for Specialized 135mm SCS system compatible frames when using a SCS 135mm road disc hub. Hanger has a 2.5mm offset to allow for proper derailleur alignment. Do not confuse with Wheels Mfg DROPOUT-146, which is for Specialized non-SCS frames. All Wheels Manufacturing replacement derailleur hangers are produced in their Colorado shop to exacting tolerances. - CNC machined 6061 aluminum - Black anodized finish - (2) M3x8 Flat head screw included