I'm pretty sure this might solve your problem, http://techdocs.shimano.com/media/techdocs/content/cycle/EV/bikecomponents/SL/EV-SL-BS77-1664_v1_m56577569830628723.pdf item no.2 part no.643 4300
@Jay75 started
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I'm pretty sure this might solve your problem, http://techdocs.shimano.com/media/techdocs/content/cycle/EV/bikecomponents/SL/EV-SL-BS77-1664_v1_m56577569830628723.pdf item no.2 part no.643 4300