Shimano Un54 Tapered Bottom Bracket

This is a good quality, durable, hard-wearing, sealed cartridge, bottom bracket, with super-accurate bearings for smooth operation and improved durability, that is ideal for traditional chainsets.
It has a lightweight hollow spindle, with a square tapered spindle fitting, a maintenance-free sealed cartridge bearing assembly that keeps out dirt, mud, and water for long bearing life that is fast and easy to instal, without adjustment.
It also has a narrow body, that allows clearance for cable routing under the bottom bracket, and a mount option, with larger driveside flange, for BB mount specific front deraileurs.