The more I research some of these early 90s units, the more I wished I grabbed them when they were readily available - alas, I was too young and broke.  I'd love to learn more about this particular unit - I read somewhere that it was mainly used for language studies.  If you know more about it, that would be great.  I'd like to know how it was used for language studies.  It's just interesting to see a walkman so thin without a battery pack.