Quoted from HP: We pursued high-dimensional reality sound by employing 7N-OCC wire, which suppresses transmission loss in the wire and provides clear, wide-range characteristics, and pure silver wire, which enables vivid, extended high frequencies and improved resolution. The plug has been replaced with a silver-plated one. High-quality solder is also used. The ear-hook wire portion has been removed, but it can be used without any problems. Thank you for viewing.