The iM54 is a compact approach to audio that offers size-defying sound. Speaker connects to a computer or other USB power source via the cable to recharge the internal lithium ion battery. Remarkable design gives surprising volume and bass response in speaker that fits on a keychain. Built-in loop for clipping speaker to keychain, bag, etc. LED key light for added convenience and safety. Perfect for cell phones, iPad, iPhone, iPod and other MP3 players, any audio source.