Perfect for SHIMANO ALFINE equipped bicycles, the double pulley chain tensioner can accommodate a front chainring difference of 16 teeth and sprockets sized 18 to 20 teeth.
The new XX1 Eagle™ Grip Shift system includes new, robust internals that make it more durable and its' shifting performance more precise. But just like the original, it is total control in the palm of your hand.
- Simple and reliable square taper bottom bracket
- Replaces both BB-UN26 and BB-UN55
- Sealed cartridge bearings
- Cr-Mo axle
- For bicycles equipped with a chain case, select BB-UN300-K
- For E-type front derailleur compatibility, choose BB-UN300-E
