A compact internal Di2 battery that hides inside the seatpost or frame for a clean look, powering Shimano's 12-speed Di2 electronic shifting systems.

• Built-in (internal) type, same size as the previous model
• Three SD300 ports for simpler wiring to front and rear derailleurs
• Third port adds redundancy for 12-speed Di2 wired setups
• Compatible with the thinner SD300 wire and systems from R9250/R8150 onward
• Same fixing method as the BT-DN110