DUB™ bottom bracket adds durability and simplicity

Wider linkage ensures durability and more precise shifting

5 degrees angle for easy and fast entry

precise shifts with improved cross-chain clearance

such as their dual mode or BLE only cycling power meters

SHIMANO Ultegra Di2 R8150 Front Derailleur - 12-Speed - Braze-On Compatio_enriched DUB™ bottom bracket adds durabilityMore compact and faster than ever, the ULTEGRA R8150 front derailleur performs digitally precise front shifts under any circumstances. Combining Shimano's new Di2 platform and the road incarnation of HYPERGLIDE+, the ULTEGRA R8150 front derailleur shifts between chainrings with our fastest, most seamless action. Shimano's fastest ever front shifting, 45% faster than FD R9150 Smaller, sleeker, lighter Frontal area reduced by 33% Weight cut to 116 g Top