Vintage WW2 era sight box military gun ammo weapon case Gun Optic Survey Sight

Description

Please read this carefully.
I do not exactly know the era from when this box is or if it is United States or foreign.
It’s all steel looks like it has been painted a few times throughout its life it has a carrying strap with two different levels on it it has metal hinges and two metal clasps one of which is missing and I show this in the photos.
The inside seems to hold something very specific with little rubber bumpers to prevent it from moving around
If you know what this is please message me and tell me I would love to know myself thanks for looking