The smooth and quick shift performance punches above its weight class. The derailleur features the Shimano Shadow RD design, which gives it a sleeker and lower profile. Shimano Shadow RD low-profile design.
Rear Derailleur Compatibility: Shimano RD-R8150 Ultegra Di2 | Shimano RD-RX825 GRX Di2. Includes the bracket, the bolt that goes into the derailleur hanger, and the B-Axle bolt that attaches the bracket to the rear derailleur body.