This is a 1:18 scale M19A1 (.30 cal) ammunition can. This version does not open and is hollowed out from the bottom to cut down on cost, making them better for bulk display. You get 12 ammo cans in one set with this model.
See
my other products in my Shapeways shop for an articulated version of this model as well as 1:18 scale models of other ammunition cans and diorama pieces.