WWI Brass Trench Box -- Double-sided with mirror - marked Skultuna Bruk

Description

This is out of my husbands extensive WWI collection.  He says it is a snuff box.  Other sites on the net call it a pill box or shaving kit.
All I know is that it is sturdy, closes tight, fits in a uniform pocket and would keep all sorts of things safe in no man's land.
Made of brass.  It is marked on one side: SKULTANA BRUK and a crown.  This is a brass company founded in 1607, holding the Royal Warrant in Sweden.
The mirror is in poor condition, compared with the other one I have listed.  The inside of the other side is coated with grey.  Husband says he thinks it was originally covered with lead to prevent corrosion from the snuff.
The box itself only has scratches and dings commensurate with age and use.  The snuff side closes, but not tightly
2" x 3" x 3/4" approximately.