This is a vintage Sony dynamic stereo headphone, the DR-6M. Made in Japan, likely from the 1980s. It provides stereo sound quality suitable for studio monitoring. It features a wired connection via a 6.35mm (1/4 inch) jack interface, compatible with various audio devices. Operation has been confirmed. This is a used item stored at home. There are scratches and dirt from use, but there are no problems with the operation.