Gradual gear progression between cogs - at least five one-tooth jumps on 10-28T, 10-30T and 10-33T cassettes while still offering a wider rangeProvides secure shift ramps specifically designed for electronic shifting, whether racing road on a 10-28T or creating an all-road setup with a 10-36TOne-piece machined steel X-DOME design for weight savings10-30T and 10-36T options available in RED for the first timeDesigned for smooth and fast shifting even under pressure10-tooth start helps provide a wider gearing range10-30t12sp10,11,12,13,14,15,17,19,21,24,27,30RainbowXG-1290XDRUPC/EAN/GTIN: 710845910425