Sound Bursting Mini Speakers (7Color Changing LED) Portable speakers are small enough to take with you. Lets you share your music with others. Great for use with portable music players or notebook computers. Designed for playing audio from your laptop, iPod, iPhone or other MP3 or MP4 players. Just plug speakers into the headphone jack of your device. Powerful bass sound fills a room. Twinkling LED marquee displays 7 colors. Built-in retractable audio/charging cables for easy portability. Keeps cables from becoming tangled. Built-in rechargeable lithium battery saves on battery replacement. Power output is 3.4 watts RMS (2 x 1.7 watts).