The Smart System - Bosch 4A Charger is the perfect charger with many advantages: It charges quickly, is easy to use and is visually impressive. The small and compact lightweight is ideal for on the go and supplies the PowerTube 750 with the necessary energy in no time: It takes six hours to fully charge, and a little more than two hours for 50% of a battery charge. A good opportunity for a soothing rest in between.