The second line in the censor's box appears to be Überwachungsstelle, i.e. "supervisory department." I still can't read the last line.
The last line is supposed to say which army corps the censor department belonged to, but the number is illegible.
Thanks JMH
The rectangle says : GEPRÜFT ÜBERWACHUNGSSTELLE KONSTANZ XIV. ARMEEKORPS I included another picture that you can read . TESTED MONITORING POINT KONSTANZ XIV. ARMY CORPS
Excellent. Thanks!
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