I bought this to install in the dashboard of my 1975 Plymouth Duster. 10 out of 5 stars! Nothing about it feels "cheap"What they do not tell you is that there is a 3. Its hard to find functionality in the app when the heart rate sensor works so poorly. GOOD1. If they are available in the future, I will purchase another pair. It does work with my iPhone which is why I gave it 2 stars. It certainly boosts the signal well. I absolutely love this rack. Und das Design, dass die Ohren auf einer extra-Line angebracht sind.