The HOTT portable CD player provides more rapid and stable Blue connection and be easily paired with Bluetooth headphone or speaker. (NOTE: this item is not compatible with smartphone and may not be compatible with some car system Bluetooth) It comes with 1000mAh Li-ion battery providing power for 7 hours at medium volume after 3-hours'fully charged. Charging with the USB cable. Does not need AA battery or external power source anymore. This lightweight CD player offers all standard playback features you would expect, including volume control, skip forward/back, play/pause, key lock, anti-shock and so on. Designed with Anti-shock Protection, which provides a stable audio experience when moving with up to 45 seconds anti-skip protection for CD and 120 seconds anti-skip protection for MP3. Compatibility: CD, MP3, CD-RW, CD-R and WMA. / DIR: Only for mp3 disc / 5 Sound Effects: BBS, Pop, Jazz, Rock, Classic.