During World War II, Germany maintained comprehensive lists of enemy weapons which were given designations in German in a system that matched that of German weapons.
When these weapons were captured and put into use with German forces they were referred to by these designations.
Before the war began the German armed forces Heereswaffenamt compiled a list of known foreign equipment and assigned a unique number to each weapon.
The Germans also captured large amounts of foreign equipment during WWII that they tested and cataloged using the same system.
The format for these designations is made up of the following elements: As an example, "9 cm Flak M12 (t)" is a Czechoslovakian 90mm anti-aircraft gun Model 12.