Shimano Ultegra RD-R8150 Di2 Rear Derailleur 2x12 Speed Shadow RD

Now simplified with a single derailleur cage length, the 12-speed Shimano ULTEGRA R8150 rear derailleur packs fastest, most precise shifting into a more approachable option. With fastest, most accurate shifting, the 12-speed ULTEGRA R8150 rear derailleur is more versatile than ever thanks to a single cage length option that is compatible with 28-34T low sprockets. Features Fastest ever rear shifting, 58 % faster than RD-R9150 Compact design includes an integrated wireless unit, charger, and switch LED status indicator Technologies E-Tube E-TUBE is Shimano's ''service'' that uses websites or apps to maximize the enjoyment of riding a bicycle by connecting the riders, the bicycles and SHIMANO. Direct Mount Rear Derailleur Rear wheels are easier to remove with a mounting option for SHIMANO SHADOW RD and SHIMANO SHADOW RD+. The direct mount feature is designed to suit a wide range of contemporary frames with large-section chainstays, in particular mountain bikes with thru-axle dropouts. Allows for flexible frame design. No special tooling requirement (M10x1 Mount bolt, without e-clip). Easier to install rear wheel. SHIMANO SHADOW RD The mechanism rear derailleur, SHIMANO SHADOW RD, is intended for more aggressive riding. Its super low profile design carries many benefits. Because of its low profile and single tension construction, the derailleur does not hit the chain stay in rough riding conditions. The result is smooth and silent performance.
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