Shimano BB-UN300 bottom bracket British thread, 73 - 122.5 mm (LL123)

A good quality bottom bracket for traditional chainsets Super-accurate bearings for smooth operation and improved durability Durable, hard-wearing sealed cartridge bottom bracket with square tapered spindle fitting Maintenance-free sealed cartridge bearing assembly keeps out dirt, mud, and water for long bearing life Fast and easy installation without adjustment Narrow body allows clearance for cable routing under the bottom bracket