Surrogate officers map case 1941 year dated

Soviet surrogate command crew map case, "surrogate" means that the leather was replaced with artificial materials. The bag is made of "Kirza" (instant leather)  and this type of bags were produced between 1940-1941 year. This example has unclear round stamp with unclear visible year. We can recognize 1941, but it's faint. Nice worn condition, with some minor age patina on the steel parts. Fully functional  mapcase