Product purchased primarily for its FM radio function (30 presets!) And incidentally some music files mp3 / m4a & podcasts. Comply with the order; work properly on Mac OS (10.6.8); the sound is good; its small size makes it convenient to slip into a pocket. I do not put 5 because I am disappointed with the helmet, the unique shape of the ear is not really suitable to my ears (it tends to spontaneously fall too easily). I'll probably have to buy a helmet that suits me more in shape.