German MG08 and/or MG08/15 Spare Parts Box (MG08 Kasten für Ersatzteile). The fieldgrey painted steel box is marked with an 'E' and '08' indicating that it would contain spare parts (Ersatzteile) for the heavy MG08 machine gun. The metal box still retains most of its original field-grey paint and white markings and is in overall good used condition, see photos. Rare and hard to find original box!