This is Sony Kimber cable for a Sony MDR-Z1R, MDR-Z7, MDR-Z7m2. Part number: MUC-B12SM1
It is 4ft. unbalanced, with 3.5mm termination
People report that they hear tighter bass, and cleaner higher frequencies than with the stock Sony cables. This cable has the the screw-on connectors for these Sony headphones, and are a nice improvement of the stock cables.