I’m not sure about most of the details of this particular pic, but shock troops in WW1 would coordinate their attacks very tightly, down to the minute, making watches a necessity.
The square device is likely a flashlight for night attacks, similar to this one:
I’m not sure about most of the details of this particular pic, but shock troops in WW1 would coordinate their attacks very tightly, down to the minute, making watches a necessity.
The square device is likely a flashlight for night attacks, similar to this one: