Installation:
Works first first with any Bluetooth enabled mobile phone. When installing there were no problems at all. Everything happened very quickly and by the instructions for use (felt in 20 languages) easy to install.
Handling:
Very easy to install under the visor and if the phone rings Pressing denHauptknopf on the device and you're connected. No fumbling or misleading stressful conversation assumptions.
Voice quality:
If there were 10 stars I would distribute them for it. My counterpart hears me better than me on my cell phone connected to the device. The opposite can be heard loud and clear.
Battery - Power supply:
I can make calls with the device without plugging it to the cigarette lighter with the supplied cable nearly 5 hours.
Price / performance ratio:
More than adequate. For the price gets not often a good device. I use it for 1 month and I'm still so well satisfied as at the beginning: