Shimano Tiagra 10-Speed Rear Road Bicycle Derailleur - RD-4601 Rear Derailleur (10-speed) Compatible for triple Crankset 30T Max low sprocket: 30T (SS, front double), 30T (GS, front triple), 32T (GS, front double) Total capacity: 34T (SS), 40T (GS) (front triple), 37T (GS) (front double) Wt: 266g (SS), 275g (GS)