Probably the cheapest route, to go, is purchasing portion cups, as enclosures, for wee slings. Also used are the dram bottles/vials. However, I do like looking around for small containers that can be used as decent enclosures for wee slings. In another thread, I showed one type, of container, that I use for them. Those are a bit larger than what I am showing in this thread. Yesterday, I came across, and purchased, these very little, see through, containers. Only one dollar for a pack of ten containers. Purchased at the Dollar Store. I did wonder if, perhaps, the lids may not close well but, surprisingly enough, the lids do close up fairly secure. They are not made of flimsy plastic either. These can work well for tiny terrestrial slings. Regular lighter, in photos, for size reference. I did measure them, though, and dimensions are: 2 3/8" L, 2" W, and 1 3/8" H.