Custom Piece – German Empire military flag Iron Cross from the World War I era – 3D Print for LEGO minifigure

The “German-Military Flag” with an “Iron Cross” from WWI, especially one referenced as a “Navy Cross Ensign,” most commonly refers to the Reichskriegsflagge (German War Ensign/Flag). Key features of this historical flag are:

• A white field.
• A black Nordic cross (often with a central disc featuring the Prussian eagle).
• The German Imperial black-white-red tricolor in the canton (upper hoist corner).
• An Iron Cross symbol, typically featured within the tricolor canton or sometimes as the pattern for the main cross itself.

It’s also possible, though less likely for a general “military flag,” that it could be a simpler banner where the Iron Cross is the primary or sole charge. However, the “Navy Cross Ensign” hint strongly points to the Reichskriegsflagge.

Therefore, if the image were visible, you would expect to see a small flag for a minifigure with these characteristic German military markings from the WWI period, with the Iron Cross being a notable element.