Here is a box for 25 cartridges in 6 mm Velo-Dog caliber, by UEE. The cases are headstamped UEE but most probably they were made elsewhere (SFM?).
All the cartridges in the box have their primers weakly snapped as if someone had tried to fire them in who knows what gun.
The tax stamp pasted on the sides dates this box between 1897-1916.