There have been several revisions to the ubiquitous and ever popular HD600 - as well as there should be considering it's 2 decade lifespan. However, I'm less concerned with the drivers in the headphones as I am with the color. Sennheiser changed the color from their Steel Blue (Or Blue Steel, depending on where you look. Zoolander fans should get a good giggle) to the Black color they have now, and I actually much prefer the blue of the older models, which have become incredibly hard to find online. So if anyone has a well taken care of pair, WITH accessories and box, I'm very interested. Pet free and non-smoking homes, CONUS only. Looking at around $200 shipped, price is negotiable.