Original 10 line unit produced in 1941. This would have been one part the the larger field switchboard. It is not designed to interface directly with the normal 10 line switchboard. The Grosse Feldklappenschrank was very modular in design with various units that could be assembled in any number of ways to best suit the requirements wherever it was installed. This is one of the more standard components in the system and it is designed to be stacked with other similar units to create large networks. The line numbers go from 11-20. It is interesting because the white fields above the lines are still filled out in German. This is likely a vet bring back. Part of this strip was covered in paper and then line names written on that. It is marked TROP on top for tropical. This doesn't mean it went to Afrika, but it was rated for that climate.
THIS UNIT HAS NOT BEEN TESTED! I can not confirm whether or not it is in working order. I will say that based on appearances it has been stored and handled well and based on experience I would say it is likely at least mostly working but that is no guarantee, just my best guess.