[nebnacnud]

I have the normal HD201 in my hand right now, they also have three metal sections on the jack / two plastic separators.

 

[PeterK445]

I have both the 201 and 201S phones. The are exactly the same except for the packaging. If you are careful when opening the blister packaging, you can use it as a storage case.
 
The audio performance is the same too. I tested them with a signal generator and a sound pressure level spectrum analyzer. No discernible difference.
 
Sennheiser always makes very good product. I have some of their microphones too. Very popular in recording of live classical music and choruses as well as broadcasting studios.

 

[Boochie]

I have the HD 201S model. Not sure what the S stands for either. The cord is straight but then again I think all 201 models have straight cables. I bought mine off a eBay seller about a year ago for $20.00.  The earpads are kind of small for my ears which makes them somewhat uncomfortable and close to being an on ear model. SQ is good I can't help but wonder how they would be if Sennheiser had only made the earcups about 1/2 inch larger and the ear pads were a little softer. How much more would that have cost?  $5.00 maybe ?
 
Anyways, they have HD201S printed on the side of it. I can take a picture if it and post if someone wants to see them.