Shimano Di2 EC300 Charger Guide

Quick Answer

EW-EC300 is Shimano's Di2 charging connector for newer 12-speed Di2 road drivetrains. Shimano describes the EC300 charger cord as attaching to the rear derailleur and also notes use with Shimano power meters.

For ALLTOOcontent, the safe angle is a buying guide: help riders confirm whether their bike needs EC300 rather than an older BCR2-style charging device.

What EC300 Is Used For

Use case	Buyer check
12-speed Di2 road drivetrain	Confirm the bike uses the EC300 charging connector format.
Rear derailleur charging point	Check the charging port location and shape before buying.
Shimano power meter charging	Confirm the exact power meter model and connector need.
Travel charging	Check cable length and adapter needs before packing.

EC300 vs Older Di2 Chargers

Many riders search for a Di2 charger without knowing whether their bike uses the newer EC300 charging connector or an older SM-BCR2-style device. The page should make that difference clear early because a wrong cable creates immediate frustration and returns.

Buying Checklist

Confirm your drivetrain generation before purchase.
Check whether your charging port is on the rear derailleur.
Confirm connector shape from your current cable or bike manual.
Do not assume all Di2 chargers are interchangeable.

ALLTOO Product Angle

Position the ALLTOO EC300-compatible adapter as a practical replacement or spare charging accessory for riders who have confirmed the EC300 format. Use compatible wording and avoid official Shimano language.