1944, war navy, registered fieldpost letter to the Office army postal service no. M 54181 ( = command 20. U boat flotilla) with mute postal stamp from 15.7.44 and fieldpost R-slip of paper with overprint "Fp XIII" ( = navy field post office Gotenhafen 1) as well with service- and cover stamp army postal service no. M 43168 = leader of the U boat training flotilla, two-sided opened, otherwise but good condition, Michel 250, 00