UwaterK7 -Smallest 100% Waterproof Swim Digital PLL FM Radio & Earphones Digital Auto/Manual precision tuning + 19 station preset Clear FM reception indoor/outdoor world wide 100% waterproof stereo earphones and 4 sets of silicon eartips are included Continuous play time of 6 to 8 hours on a single charge - built-in Lithium-Ion rechargeable battery (USB Cable included). Radiofrequency: FM 88-108 MHz - at or above water's surface