This is the 400-BTTWS4BK, a completely wireless headset from SANWA SUPPLY. It supports Bluetooth 5.0, has a communication range of 10m, and a continuous playback time of approximately 5 hours. It comes with a transmitter and can be used with various devices. [Brand] SANWA SUPPLY [Model Number] 400-BTTWS4BK [Connection Method] Bluetooth 5.0 [Communication Range] 10m [Continuous Playback Time] Approximately 5 hours Although it is unused, it has been stored at home, so please purchase only if you understand this. Thank you. I purchased this for my mother, but she won't try it, so I am putting it up for sale. Thank you.