Lightweight design and flexible headphones with ergonomically-shaped ear pads and foldable, swivel design affords easy portability that has an adjustable headband. It has 30mm drivers and neodymium magnets for powerful sound, you'll enjoy powerful bass and crisp, clear highs. You can listen to music with a battery in (stereo mode) or not (passive mode) and the sound is very good when used without a battery. It's in very good and clean condition and have been cleaned and sanitized with rubbing alcohol. It has 80hrs of battery time with one AAA battery.