performance in question

Have bought the adapter to connect to my Medion Navi over an angled USB cable. The original Medion-car charger has significantly lower power values ​​(800mAh and max. 1.0A) yet the battery with the original adapter of Medion at the same time the instrument is switched within 1hr. Trip fully. With the Wicked Chili adapter, the battery is not fully charged even after 2.5 hours. Charging time. So the adapter is sufficient for the operation of the navigation system, but not for the same time recharge the battery. Therefore, only 2 stars. Disappointing for the high price.