Specification: Adds security to \"narrow/wide\" 1x10/11 and XX1/X01 drivetrains,Most models accommodate 26-38t chainrings,Tracked and grooved upper guide / backplate interface increases stiffness and eases installation,New co-molded \"TR\" upper guide with softer durometer interior for silent guidance,Available D-Mount (FD), Carbon D-Mount, E-Mount/S3 (FD), Seat Tube (for MTB and CX), ISCG-05, ISCG, and BB mounting options,All install and adjustment operations possible with just a single 4mm HEX wrench.,39 (S3) - 74g (Seat tube MTB),Seat Tube mounted versions use first generation (V1) upper guides,CX model is only compatible with two-ring, road crank chainlines, BB mounted guides are only compatible with traditional, threaded BB systems.