Very good price / quality ratio, although chromium actually did a little OCD. At that price should not ask too much either :-) I had just qques difficulties for the sail on my phone. If AC can be used to qqu'un here is the manipulation that I found: - Turning on the headset and keep your finger on the on / off button - Start the analysis from such, while leaving the finger on the headset. In qques seconds the equipment is done.