German troops wearing body armour in a trench. Note a stirnpanzer brow plate on the helmet of the soldier on the right.
I wonder how effective it was against direct hits or more for fragments?
They were primarily issued to snipers, trench raiding parties and advance sentries so I’d assume they’re more for bullet protection than anything else. Helmets themselves were usually enough protection from shell fragments. They also weighed about 2kg so they’re not really designed for prolonged wear.