A: Sprocket Wheel 11T CS-M7000/CS-M8000 (Built in spacer type)
B: Sprocket Wheel 13T CS-M7000/CS-M8000 (Built in spacer type)
C: CS-M9100 Sprocket Units, 10&12T (Fits Deore, SLX, XT & XTR 12 speed cassettes)