Long Battery Life No need to replace the battery for about 2.5 years! Although the purchase date is unknown, it has been stored in a dark place without being used. Although it is new and unused, as shown in photo 6, one AA alkaline dry cell battery for operation check is removed. 〈Contents〉 Mouse body × 1 Receiver unit × 1 User's manual × 1 I am completely unfamiliar with PC-related matters, so I may not be able to answer your questions. Please check the photos for details such as supported OS and product specifications. Please understand that this item is stored at home before purchasing.