Shimano - M3100-SGS Alivio Rear Derailleur Bottles Shortfit features the side profile

Shortfit features the side profile of the seating surface with a central depression of more than 5 mm that is similar to a curved line

but doesn’t skimp on toughness

No matter by which means and where you’re heading

14-tooth X-SYNC™ lower pulley easily facilitates 11- to 50- and 10- to 50-tooth cassette capacity

Shimano - M3100-SGS Alivio Rear Derailleur Bottles Shortfit features the side profileSHIMANO ALIVIO Rear Derailleur SHIMANO SHADOW RD 9 speed The SHIMANO ALIVIO M3100 rear derailleur delivers a low profile design that lets you ride aggressively with fewer interruptions thanks to its SHIMANO SHADOW design. Low profile design Total capacity: 45T Max. low sprocket: 36T Adjustment barrel