This is an external dry cell battery case EBP-25 for SONY CD Walkmans. It uses two AA alkaline batteries. Therefore, it supports models that use two gum-type nickel-metal hydride rechargeable batteries in the main unit. [Contents] EBP-25 body x 1 [Main Compatible Models] D-E888, D-E-999, D-EJ700, D-EJ800, D-EJ855, D-EJ885, D-EJ-955, D-EJ985, D-EJ1000, D-NE800 [Operational Status] After installing two new AA alkaline batteries, the following checks were performed and confirmed to be working properly: ① The voltage between the connection terminal (inside the square type) and the outer metal part (GND) is 3.16V (voltage when two dry cell batteries are connected in series). ② It works normally when connected to a D-NE800, and the battery mark is MAX. [Appearance] There is some wear and tear, but no noticeable scratches or stains.