Shimano ultegra br 6403 brake blockssuitable for standard shimano road caliper brakes and for use with aluminium rims featurescompatible with the following shimano modelsbr 6403br 4400br 3300br 1055br a550br a450br a416br a410br a350br a250a 2 year warranty is offered with all shimano products from chain reaction cycles 3 years on dura ace and xtr products buyshimano componentsfrom chain reaction cycles the worlds largest online bike store