The Shimano SM-BTR2 is a rechargeable internal battery for use with Dura-Ace 9700 Di2 and Ultegra 6070 Di2* component systems. It's installed inside the seatpost, and accommodates a wide range of sizes thanks to the included slotted shims. It can be charged using the port on EW90-A/B cockpit junction box or SC-705 display unit, and requires the SM-BCR2 charger.
The SM-BTR2 weighs 56 grams and charges in approximately 1.5 hours. Its charger (SM-BCR2), wiring kit, and frame mount are sold separately.
*Requires a firmware update. You will need the SM-PCE1 PC Tool to install this update, which can be downloaded at http://e-tubeproject.shimano.com. Alternatively, the most recent firmware can be installed at your local Shimano Service Center.
The product weight specified is an approximate weight based on the manufacturer's specifications (if available) or our measurement of one or two examples. For most products, the weight will typically vary by 5% to 10%.