Shimano Ultegra Di2 ST-R8170 12 Speed Shifter + Flat Mount Caliper Size:Rear Brake - Left Hand Dual locking Presta/Schrader nozzle

Dual locking Presta/Schrader nozzle

4 mm thick square chain with textile sleeve that prevents damage to paintwork

reliable shifting

Hardened bolts hold securely and make chain replacement easy

Shimano Ultegra Di2 ST-R8170 12 Speed Shifter + Flat Mount Caliper Size:Rear Brake - Left Hand Dual locking Presta/Schrader nozzleRoad riding has never been this much fun. The redesigned Shimano Ultegra Di2 ST R8170 12 Speed Shifter and Flat Mount Caliper has all new ergonomics, even more precise brake modulation and wireless electronic shifting, letting you focus on the next sprint, the next descent, or the next joke from your riding partner. Shimano's ULTEGRA ST R8170 brake levers bring enhanced modulation and control to every ride using Shimano's proven SERVO WAVE technology.