The 4A Charger is the perfect charger with many advantages: It charges quickly, is easy to use and is visually appealing. The compact and lightweight charger is ideal for when on-the-go and quickly supplies the PowerTube 750 with the necessary energy: It takes six hours to fully charge the battery, and just over two hours for a 50% charge. ?FEATURES: Compatible with components of the smart system Charging time for PowerTube 750: 50% in approx. 2.3 hours, 100% in approx. 6 hours Charging current: Max. 4 A AC rate voltage: 100-120v Cable lengths: Power cable: approx. 1.5 m, battery cable: approx. 1.0 m Please note: the smart system is not compatible with the Bosch eBike System 2