Sony Walkman (Horwich BL6)

I've inherited this Walkman and it seems to work. The leaflet refers to a Digital Media Player Active Speaker Kit. All I know is that I've been able to charge it and there are a few songs on it. It should be possible to link to a pc and then download and play your own music. It's probably about 15 years old, in very good condition but I can't guarantee that nothing is missing.