Arriva is, in this case for players, upper 1 GB iPod Shuffle, parked in a safe port into the earplugs behind the head stents, convenient. The price of itself in ear plugs $35 or so, but this system also need to purchase a shuffle, increased the overall costs $35. Shuffle is limited, its function sets, but as a special part of the operation of the system, it is very difficult to defeat.