an apparently undocumented G80-1134 HAX built in 1988.
"Apparently undocumented" because even if Wodan found a keyboard with that exact article no. in one of his legendary recycling center raids, this one features quite special, dual keycaps. And it has its original cord, is fully functional and has vintage MX black switches so smooth that even I feel the difference

Manufacturing date: A30, i.e. somewhere just past mid-1988: .
Date stamps in the upper and lower shells: .
Top view of the keyboard: .
Bottom view: .
The PCB shows all switches are equipped with diodes, so the keyboard has NKRO: .
Both "delete" keys (in the sixpack and the numpad) are labelled "Lösch" instead of the usual "Entf": .
Last, but by far not least, the keycaps are German layout, but are also front-printed with (obviously also doubleshot) English legends: