SHIMANO Bottom Bracket BB-UN300

Shimano's Square Taper Bottom Bracket BB-UN300 is a standard BSA-style bottom bracket available in various shaft lengths.

The BB-UN300 Square Taper Bottom Bracket is Shimano's successor to the BB-UN26 and BB-UN55 models that were previously manufactured.

The BB-UN300 has BSA standards and is available in a variety of different axle lengths, covering a wide range of bicycle types from touring bikes and city bikes to old road bikes and mountain bikes.

*Crank bolts are not included.

SPEC

Type: BSA
Shell width: 68mm
Axle length: 107mm, 110mm, 113mm, 117.5mm, 122.5mm, 137mm
Axle type: Square taper (JIS)
Bearing: Steel
Axle material: Steel
Bottom bracket cup material: Aluminum (left), Aluminum/ Steel (right)