Walkman 40th anniversary just something like this?
Looks like purely an engraving service for the A series
"Walkman marks the 40th anniversary on July 1, 2019 ® .
With gratitude to the patronage of our everyday customers, we will imprint a very popular character on the back of the A series that enjoy high-resolution, high-quality music (* 1).
Walkman ® has been loved just as many years with Disney "Mickey Mouse", you can choose your favorite character from the PEANUTS "Snoopy", and "Relax".
With characters who are enjoying in each style, now also music is much Walkman ® in.
[Service charge] 2,500 yen
[target product] Walkman ® A50 series (* 2): NW-A55, A55HN, A56HN, A57
[period limitation] until Monday, September 30, 2019 10:00"
nice find though