BT-DN300 Di2 Battery

The new DN300 Built-In type battery features the same waterproof design that Di2 users have loved for generations. Now with 3 ports, it delivers stable power to Shimano's 12-speed road derailleurs (and shifters if a fully wired option is selected).
• Compatible with thinner next generation electric wire SD300 and systems after R9250/R8150 series
• Li-Ion type
• Capacity: 500 mAH / 3.7Wh (± 2000km autonomy)
• Rated voltage: 7.4V
• Charges through RD-R9250 / RD-R8150 rear derailleur using EW-EC300 Di2 Charging Cable (sold separately)
• Fixing small parts included
• Weight: 52 g