Shimano acera m3000 triple chainsetthe shimano acera is designed for entry level mountain bikes but thanks to a trickle down effect entry level riders profit from innovations made for high end group sets please note bottom bracket is not included features 9 speed 40 x 30 x 22t compatible with es51 octalink bottom bracketa 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