PRO Di2 Internal Battery Holder for Fork Steerer

Routing a Shimano Di2 battery inside a fork steerer keeps your build clean and your seatpost free for other purposes — the PRO Di2 Internal Battery Holder for Fork Steerer is the hardware that makes it work. The mount is a two-piece cylindrical shell: the battery sits inside the halves, and the whole assembly slides into the steerer tube. Ribs on the exterior compress slightly to fit minor diameter variations in standard 1-1/8" round steerer tubes.

Before you commit to this routing, a few things to verify: the Di2 battery measures 152mm long and 16mm in diameter, so your steerer tube needs at least an additional 20mm beyond battery length to accommodate the holder. You'll also need Di2-compatible cables, a Di2-compatible stem and top cap, and handlebars with the small wire ports required for internal Di2 routing. With the right setup, it's one of the tidier ways to tuck the battery out of sight entirely.

PRO Di2 Internal Battery Holder Specs at a Glance

• Compatibility: Shimano Di2 internal battery
• Steerer fitment: Standard 1-1/8" round steerer tubes
• Battery dimensions: 152mm x 16mm (minimum steerer clearance required)
• Mount design: Two-piece cylindrical shell with compression ribs
• SKU: PRAC0085