The product is a vintage Sony tape cassette-corder microphone battery pack model BP-40, designed for use in the 1970s. This battery pack has been tested and confirmed to be in working condition. As a part of vintage audio and video equipment, this Sony BP-40 battery pack is a rare find for collectors of retro electronics. It is a crucial component for any vintage cassette deck or audio device that requires a reliable power source. *Turns on plays with sound
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