Check the listing for details. Sony ORIGINAL Walkman AA Battery Case Attachment with DC IN 1.5V. Color: Black, Condition: Used. Listed at 30.90 USD. AA External Battery Power Pack for SONY MD Mini Disc Playernot including AA battery Note,this Battery Case with DC Input.Compatible with WM-EX600 EX610 EX621 EX631 WM-EX655 EX651 GX788 FX700WM-EX808 FX833 EX633 FX811WM-EX666 EX511 EX555 WM-GX760 GX674 GX688 GX808WM-EX88 EX77 EX808 FX77WM-FX653 GX654 GX614 FX513WM-GX652 EX9 EX900 EX7WM-FX707 FX808 FX877 FX888WM-EX909 FX909 FX999 WM-EX922 EX911 FX805WM-EX501 EX530 EX677 EX615WM-EX66 FX777 RX707 RX77WM-EX910 EX2000 EX921 WM-GX711 WM-EX622 WM-FX822 WM-GX822 WM-FX833 WM-RX822 WM-GX655 WM-GX622 WM-EX641 WM-EX642 WM-FX855 WM-EX677 WM-GX677 WM-FX877 WM-EX600 WM-WE01 WM-EX910 WM-GX688 WM-EX2000WM-EX631 WM-EX621 WM-EX651 WM-GX788 Package includes： 1x original SONY AA Battery case（not including battery）