Kensington FX 500 Speaker to Go Case for iPod and MP3 Players (Black) Ultra-thin, lightweight design makes it easy to throw in your bag and take with you iPod and speaker controls accessible from outside for ultimate convenience Battery operated for 10 hours of continuous play at high volume Universal compatibility with non-iPod MP3 players; Compatible with iPod Shuffle; iPod Nano (Gen 1,2,3); iPod (Gen 1,2,3,4); iPod Classic Dual integrated NXT exciters for clear, loud stereo sound