This is a shoulder-mounted speaker from SONY. You can listen to audio by transmitting it wirelessly using the dedicated wireless unit. I purchased it for use with Final Fantasy 14, but due to the noticeable latency, it wasn't suitable for raid race environments, so I'm selling it. (An environment requiring latency of around 1ms is necessary. It should be fine for general use.) The sound quality is quite good, and it has a surround sound feel, so it's a good option for audio listening. It's a bit heavy, so it might not be suitable for everyone for everyday use. It hasn't been used much, but the outer box is missing, and the sale includes only the following items shown in the product photos. Please note: * Main unit * Charging unit for the main unit (USB cable and a general-purpose charger are required) * Optical digital cable * Transmitter (USB cable and a general-purpose charger are required) Please refer to the official website for the manual. Please prepare the various USB cables yourself.