Shimano BMR1 and BRM2 Di2 External Battery Mount Base Unit A CheckoutSpec= and Bushing Assembly Kit High grade polymer pulley wheels

High grade polymer pulley wheels (12T upper 14T lower) allow for smooth chain running and secure retention

Safety is the key with integrated reflectors and a LED taillight at the back ensuring high visibility of the cyclist during the day and night

safe riding experience for kids

Front/Rear RR Cassette Body/Freehub 3s Int Hole Count 32H Spacing/Axle B/O-NUT 3/8x26t Material Aly Color Sil Weight 1080g Brake Type 6B Spacing 135 PCD-L PCD-R LTF-L LTF-R CTF-L CTF-R

Shimano BMR1 and BRM2 Di2 External Battery Mount Base Unit A CheckoutSpec= and Bushing Assembly Kit High grade polymer pulley wheelsShimano Di2 External Battery MountsAll Di2 components on the bicycle require the same firmware version. Using Di2 components with different firmware versions may cause malfunctions Use Di2 system checker to update component firmware from http: e tubeproject. shimano. com