Shimano i spec b bolt nut unitthis bolt and nut unit is a replacement for the set supplied with the i spec b compatible shifters the kit enables the rider to mount the i spec b shift lever to an i spec b compatible brake lever alternatively this kit can be used to fit i spec b shifters to i spec a brake levers compatible shifters slx sl m670 b xtr sl m980 b xt sl m780 bsaint sl m820 ba 2 year warranty is offered with all shimano products from chain reaction cycles 3 years on dura ace and