This walkman uses two standard AA size batteries for power.
Type of restoration done: Rubber drive belt was replaced, after the replacement the speed was adjusted properly with Sony Professional test tape at 3000Hz. Other smaller steps as necessary to restore each walkman are also done but I don't describe those in each listing.
ABOUT THE RESTORATION: Why is it important for the item to be restored? If you are buying vintage electronics that were NOT restored (no matter if used or brand new sitting in the box) and the sellers state were tested and work, you should know that they don't work as good as the day they left the factory without the need of any restoration work done. You should know that it is extremely rare( 1 in 10 or 20 chance) to see a vintage item working PERFECT after sitting for some 20+ years without the need of any restoration work done. This is because rubber gets old, plastics shrink and crack, electronic components that have liquid in them won't give the same performance as freshly made ones, etc. That is why it is important to buy an item that has been checked and restored. Repair places don't do restorations but just fault finding. They just find what electronic component is causing a device to malfunction and replace that component only. This is because it takes a lot of time to restore an item and unless you ask and are ready to pay, they won't do it.