I have stored this at home for a long time. I have confirmed the following. Please consider everything below. It could be charged. Music could be added. Music and radio could be listened to with earphones. Music could be listened to without earphones using the built-in speaker. Button operation is problem-free. It supports Bluetooth. The contents have been deleted. When I tried to initialize it, a message saying "restored" appeared, and I couldn't initialize it. It was fully charged around noon, but all the charge was gone the next morning even though it wasn't used. There seems to be a problem with the battery life. Therefore, I am selling only the main unit as a junk item. Thank you for looking.