Unopened Sony Master Carton - WM-EX660 (NOS)

Hi everyone,

I would like to share a recent find from an old Sony Europe stock.

It is a factory-sealed Master Carton of the Sony WM-EX660 (Black version), containing 10 units. The carton is still secured with the original Sony-branded adhesive tape and has been stored in a controlled environment.

As this is a "Case Fresh" lot, the internal units have never been exposed to light or dust since they left the factory. I thought this community would appreciate seeing a documented example of a full, intact factory block in 2026.

I will attach some photos of the seals and the original labeling for archival reference.

Best regards,
Mazziesco

 

I wonder what condition the belts and gumstick batteries will be in after over 25 years ?

Thinking back to what I was doing around 1999 I bought my first mobile phone that year although since it didn't play music it wouldn't have replaced a Walkman.

 

That is a very good point regarding the belts and batteries. Given they have been sealed since the late 90s, it’s highly likely the belts will need replacement and the original gumstick batteries may no longer hold a charge.

However, for a find like this, I believe the primary value lies in the 'factory-sealed' integrity of the Master Carton and the individual boxes. Opening them to check the belts would destroy the 'collector grade' status of the lot. I prefer to leave them as a time capsule for the next owner to decide whether to preserve them sealed or perform a professional restoration.

And you are right about 1999—it was a true turning point before everything went digital!"

 

Great find. Speculations about forgotten containers somewhere in a harbor area full of new Walkmans or boomboxes have been circulating for years.

My experience with NOS hasn't been good. I've often seen that the Styrofoam packaging material has started to chemically react with the contents after all these years. That they've melted together. Back in the day, they didn't always put a plastic bag around the object to protect it. Those were things from the '80s.

These days, the value lies mainly in the influencer who is willing to spend a lot of money to put themselves in the spotlight by opening it in front of their audience.

Thanks for sharing. Always cool to see something like that!

 

Thank you for the insight. You’ve raised a very interesting point about the chemical reactions with styrofoam, which was indeed a major issue for 1980s units.

Fortunately, by 1999, Sony’s packaging for the WM-EX line had evolved. Most units from this era were protected by inner cardboard structures and anti-static plastic sleeves, which significantly reduced the risk of 'melting' or chemical bonding with the outer casing.

As for the 'influencer' aspect, you are absolutely right. The appeal of a 'time capsule' unboxing is huge today. While it would be a unique experience to see one of these opened live, I still believe the integrity of the sealed Master Carton is a rare piece of history on its own.

I appreciate you sharing your experience with NOS!

 

Belts are gone and gumstick are packed in a small battery carrying case so protected and far away from the walkman. Would love to open that box up!!

 

It is great to know that the gumstick batteries in this model are likely stored in a separate carrying case—that gives me much more confidence regarding the internal condition of the units.

I definitely understand the temptation to open the box! The curiosity is huge for me too. However, as a collector, I feel that the 'factory seal' is a one-way street: once it's gone, it's gone forever. For now, I think the most respectful thing to do for this find is to keep it intact as a complete 10-unit Master Carton.

It’s a true piece of Sony history, and I want to preserve that 'unopened' mystery a bit longer!

 

You hit the nail on the head—it really is the ultimate dilemma for any collector. However, I agree with you: the 'premium' of an untouched, factory-sealed package is something that can't be restored once opened.

I've heard about similar legendary finds in the past, and it's fascinating how much interest they generate. It's almost like 'Schrödinger's Walkman'—as long as it stays sealed, it remains perfect in the mind of the collector.

For now, I'm happy to keep these Master Cartons exactly as they are. Thanks for sharing your thoughts and the context about that video, it's very helpful!