This is a nasal snuff tap box. It's capacity is around 8ml. With a quick wrist flick the pea size chamber under the lid is loaded with the same size dose of
...Plus snuff each time. The snuff can then be tapped out onto your anatomical snuff box or box car.
A video demonstrating the "flick to fill" method https://www.youtube.com/watch?v=_3BoXW7x8iY