Music and swimming (or sport) in isolation from ambient noise

(+) Easy to use
(+) Hold of the atria (3 silicone molds provided with 2 waterproof)
(+) Clamp right size to attach under the strap of the mask or the swimming cap
(+) = Smart USB connection by the "helmet" jack (special cable)
(+) Waterproof
(+) Good quality sound

(±) only .mp3, .aac does not support the (.m4a apple) = requires a re-conversion if your library is on itunes
(±) time copy of files long enough.
() Special cable to charge the battery and charging the batteries: not to lose!