Brainwave Measurement Device Alphatec 4 (Noryoku Kaihatsu Kenkyujo Co., Ltd.) I received this as a gift, so I don't have detailed knowledge of it. The main unit and accessories have small scratches and dirt. Regarding operation, I have only confirmed that the main unit powers on, but I have not confirmed other functions, including software integration and measurement. Also, the small (battery-powered) battery box shows rust and corrosion, so it is likely inoperable. The earphone-type sensor used during measurement also shows signs of use. Since I cannot guarantee any of these, please understand that this is being sold as a junk item. The Alphatec 4 is a biofeedback device that measures brainwaves in a relaxed and focused state and displays graphs and numerical values on a dedicated PC software. The items to be shipped are only those shown in the photos. There may be missing items, so please check the images and consider before purchasing. Only those who understand that this is a used and junk item, please purchase.