Air release valve to easily purge the bag of trapped air

Braze-on fits frames with pre existing front derailleur braze-on (can also be used with 31

Daisy Chain for attaching a tail light or other equipment

Each mounts easily to your bike and the Bluetooth Smart and ANT+ duel band technology allows you to connect and display data on both smartphone and bike computers

tooth profile and shift ramp design for quick and positive index shifting

Shimano ULTEGRA English EXI,HOLLOWTECH-II,MEGAEXO-LIGHT,MEGAEXO 68/70mm Bottom Bracket can be discounted Air release valve to easilyWith reliable SHIMANO bearings and seals, the SHIMANO ULTEGRA bottom bracket has a long service life.