4.(M.G.) E.Kp.104 Erkennungsmarke

The dog tag or 'Erkennungsmarke' shows signs of wear. The soldier of the tag served in the 4.MG. Ersatz Kompanie 104 which was part of Infanterie Ersatz Bataillon 104. This regiment was formed in August 1939 in Darmstadt. In December the bataillon was used to form I.Bataillon Infanterie Regiment 321. In the beginning of 1940 the Ersatz Bataillon 104 was reformed again. It trained and supplied soldiers for Infanterie Regiment 104 and 629. 
In November 1940 the Bataillon was renamed into Schutzen Ersatz Bataillon 104. It trained and supplied staff personel for the 5.Panzerarmee, 15.Panzer-Division, 15.Panzer-Grenadier-Division, 164.leichte-Afrika-Division, for Schutzen Regiment 104 and Panzer-Grenadier-Regiments 104,125,382,443.
Infanterie Regiment 104, later Schutzen Regiment 104, saw combat during the Afrika Campaign since early 1941.
The 'O' on both parts of the tag stands for the bloodtype of the soldier.