Pen mp3 128mb built in flash memory (optional 256mb/512mb/1gb) High quality mp3 and wma , asf music format playback Included usb cable connector easily docks to any usb jack -without lcd display High quality digital voice recording function A-b repeat playback Usb bus battery recharge Built-in 3.7v re-chargeable li-ion batteryß -up to 8 hr mp3 playback time Upgradeable firmware included windows 98 driver Metal casing Usb2.0 full speed Giftbox:182*92*52 80pcs/caton Carton size:818*315*388 One unit weight:255.5g Gw:255.5*40+634g Nw=255.5*40