Shimano un26 square taper bottom bracket great value sealed cartridge un26 bottom bracket with square tapered spindle features great value sealed cartridge un26 bottom bracket with square tapered spindle sealed cartridge bearing assembly maintenance free sealed cartridge keeps out dirt mud and waterfast and easy installation without adjustment shell width 68mm or 73mm a 2 year warranty is offered with all shimano products from chain reaction cycles 3 years on dura ace and xtr products b