A professional horn driver unit from the musical instrument manufacturer TEISCO (TESCO) that existed until the mid-80s. I don't know the detailed specifications, but it seems to be a FOSTEX OEM product. It's a straight way to sound like a pro (Fujisawa Yukishi)
Maintenance information: 2023.6.1 operation confirmed
Accessories: none
Main specifications: 8Ω external dimensions W267 x H110 x D200 mm (actual measurement)