"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. Our fastest ever front shifting, 45% faster than FD-R9150. Frontal area reduced by 33% for a sleeker more aerodynamic design. Weight cut to 116 g."
 
- Shimano