Cervélo S3 DISC Manual De Instrucciones página 35

The battery for your Shimano Di2 system mounts inside the down tube using a battery
holder (DI-BM-INT-S5D) designed to fit this frame. As this is a sealed location, it is
important to test the system prior to final installation.
Press the two M3 fixing nuts into
the holder through the upper
holes. Attach battery to mount
using two zip ties, and install.
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