Ultegra RX RD-R8150 Di2 12 Spd. Pump Accessory an EVA foam rubber compound

an EVA foam rubber compound that is designed to mold to your heel and reduce excess motion within your shoes

8 and 28 mm are compatible

ready to roar

and feel to your game

Ultegra RX RD-R8150 Di2 12 Spd. Pump Accessory an EVA foam rubber compoundNow simplified with a single derailleur cage length, the new 12 speed Shimano ULTEGRA R8150 rear derailleur packs our fastest, most precise shifting into a more approachable option. With our fastest, most accurate shifting, the new 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. Our fastest ever rear shifting, 58% faster than RD R9150 Compact design