Shimano tiagra 4700 bottom bracketstrong and smooth the shimano tiagra 4700 bottom bracket is for use with 2 piece cap free design road chainsets featuresminimal bearing interface gives superbly smooth rollingeasy installationweight 72g approxa 2 year warranty is offered with all shimano products from chain reaction cycles 3 years on dura ace and xtr products buy shimano components from chain reaction cycles the worlds largest online bike store