Thin is in! At only 1.24" thick, Logitech's mm28 Portable Speakers are thin enough to take with you anywhere. Powered by NXT flat-panel technology, the entire front surface is a stereo speaker that produces rich tones and lush bass. It's versatile; use it with your MP3 player, CD player, DVD player, or anything else with a standard headphone jack output. Then store the 3.5 mm input jack in the back of the speaker when you're on the go. Flexible power options include an international power adapter as well as 4 AA batteries (not included) capable of 45 hours of battery life. Included: mm28 Portable Speakers, International voltage AC power adapter (100-240V).